Maybe some cast portraits, or just doodles. Everyone loves to see random doodles!

I bet people wouldn't mind paying to see your warmup drawings. Who knows, some of us might learn something from it too!

I agree with the first commenter and the ask the cast thing would also be fun to bring back. ^w^ Don't know if I got much else to suggest besides that. <w< Some possible side projects to the story maybe? Like images of scenery of all the different places in the story and what not? :3

Well.. I personally never could forget these two pages when I first read them.

http://www.furaffinity.net/view/20978132/
http://www.furaffinity.net/view/20978156/

Your patreon could be about these kind of backstories, showing a little 'extra' :P
Introduce us to This little 'arrangement' of Tobur and Runa!

I think the 1st tier should get early access to the comic before you release it publicly, the 2nd tier should get to do ask the cast, and a 3rd tier should (if possible) have cameo's in the comic. If you want a 4th tier, perhaps give them something more personal, though i'm not sure what to recommend at this level if it's only going to be there to support the creation of Forest Tails.

As an additional warning; you should be made aware of yiff party (which I won't link to for obvious reasons), a site that leaks Patreon content. If you want to truly deal with them without affecting your supporters at all, then you have to make the act of leaking your content a meaningless task (hence why your desire to not keep Forest Tails locked away on there for a year could prove beneficial in this case) as that makes only the people that would never support you in the first place go there for your stuff, while everyone else is more likely to feel it's worth supporting you (essentially turning that site into a bit of free advertisement), though this isn't guaranteed and you might lose supporters simply because they feel they can "get it for free".
The only other way to deal with them, is to enable Charge Up Front on Patreon (meaning that the moment we pledge it takes the money from our accounts on a month by month basis), and to add a ridiculous amount of watermarks (that some of us will notice and will essentially downgrade the HD versions of any pages for some) using a service like Prime Leap to do so. I'm not too familiar with how Prime Leap works, so if you have any questions I'd send them to anthemoftears as they are the ones behind the site. When it comes to the watermarks you'd need to make a different set for each and every supporter so you can learn who the leakers are and then block them, so with Prime Leap you'd have to learn how much extra work it loads onto you, before pursuing it. The only real issues with Prime Leap are how prominent the watermarks are visually for those that are able to notice such things by simply looking at the page, and the reputation of the people behind it and the reputation of those using it. Unlike Patreon, Prime Leap has a generally smaller user base right now and some of the artists do have a slightly negative reputation in some circles so for some the choice to sue Prime Leap could make them associate you with them and thus with their negative reputation.
The choice is yours, but I thought it best to voice this and give you more options. It's all about perspective and how you feel these things will affect you and your attempt at gaining financial support.

The only other advice I'd give is to do a bit of research into copyright and all sorts of crowdfunding sites as some laws could put you at risk based on basic and simple mistakes. Like I live in the UK and we have a law written for charities that says that if you say you'll spend the money raised on A then you legally have to spend it on A, you can't spend it on B as that would be illegal, which is why charities always hint at they'll use it to "help" the people, which allows them to pay an accountant to organise their finances and manage them even though that doesn't directly link to what the charity raised the funds for, it simply can make their job of organising the funds they raise easier to manage which they would argue allows them to spend it on what the cause they're supposed to help, e.g. starving children. I mention this vague law about charities because, the UK doesn't really have laws about fund raising things like Patreon or Kickstarter or GoFundMe...as they're essentially different from a charity, but because of the lack of laws directly relating to them, this law about charity fund raising could potentially be used against someones Patreon, of their Kickstarter campaign or even a GoFundMe campaign. So the reason I mention the law is to make sure you word your Patreon correctly to keep yourself from being legally liable, because while it isn't likely to happen, it's best to be prepared and avoid the possibility of the situation. Simply put when it comes to what you write on your Patreon, don't make any promises you can't keep, and keep your supporters up to date via Patreon (posting stuff here or on your Twitter might not cut it, so having updates posted on your Patreon about things that affect your ability to post are in your own best interest.

Finally, if the micromanagement of multiple sites gets to be difficult or you'd like to make it as easy as possible, then I'd recommend using the service of PostyBirb which allows you to post to multiple sites at the same time.

Hope this helps your somehow.

I wish I had more advice, but honestly I don't even want any rewards, I just want to be able to support your work! Maybe releasing one page early at a time if you feel bad about people waiting too long and still want benefits.

I generally avoid sites like Patreon out of principle. I pay for tangible goods or services, not for subscriptions. That's why I've been buying Toby apples. But, since you're setting it up as submission-based, then that changes things a bit. What would a "submission" be, a page of the comic? Would patrons be charged their tier fee for each submission regardless of how frequent they are, or is there a time-based limit? If I join the (just as a random example) $10 tier, how much of that $10 do you get as the artist?

I'm not against the submission-based Patreon, but I'd be much more likely to purchase the entire thing as, say, a PDF or something when it's done. Or, if I knew how long the comic would likely be, then I could calculate how much I'd be paying for the whole thing. I guess one of the big problems I have with services like Patreon is the huge number of variables involved. As a mathematician and analyst, I like predictability.

tl;dr
I'd absolutely pay for Forest Tails. I just have my doubts about services like Patreon.

I do agree with extra images, cast pages, and doodles!

Do you ever record your process? You could release patreon exclusive video of you working on pages as an incentive. Or you could even have a private subscriber stream where they can watch and talk with you a bit (if that's something you're into, anyway!)

A lot of people also release higher resolution and alternate versions of publicly available material, so you could post the comic and give your supporters textless/colourless versions to see. If you're not into the video/stream thing, seeing the stages of sketch to finish on pages would be pretty cool, too

Yeah, I feel like a delayed release would be the best way. I see times around 2 weeks to a month as the most common.
As for like a 2nd tier, sketches and WIPs would be good

From an aspiring artist's perspective, I enjoy when creators include work in progress and time-lapse style extras. I'd be quite interested to see how to plan out and put a page together. I don't know whether that would have enough pull to keep someone at a dedicated tier for it, but it can make for a nice supporter exclusive bonus that doesn't feel like you're blocking access to the comic itself.

For what it's worth, timed exclusivity of content has occasionally driven up my pledge amounts, but the lack of exclusivity has never driven them down. I'm honestly more happy to support artists that release their work publicly immediately, but I respect both approaches and (budget allowing) will toss some money at you either way.

Well with it being submission based I'm not sure. I suppose you could give higher tier access to higher resolution pages

Look at the people who are doing what you are doing, who are successful, and follow their lead. Go with what other people have shown to work.

You could still do a "post to patreon first, then everywhere else later" thing, but maybe instead of a month or a year, you could do a week instead?

Also, high res files might also be a decent reward. I know there are some people out there who LOVE to have the original res files of artwork, for whatever reason. So maybe thats an idea?

If you want ideas you could show line art that could have been apart of the comics. Or even early access to work documents.

I tend not to follow Patreon as standard (because i would follow too much people). I think there are ways for you to keep the comic free for the many followers but also earn something and support yourself.
1) One big point (as tier) is the Q&A: it could surely be reserved to Patreon on different degree (number of questions etc.)
2) Sure you can make an early release and show WIP.

Supplementary mini-short story(ies) could be an idea. Still I think it they could be eventually uploaded here, just with a delay compared Patreon.

Some artists use the top-tiers Patreon as commission also. You could offer the possibility to draw feral character (sketched? B/N?) retaining the style and natural-world setting of Forest Tails.

Jackaloo (you've likely already seen how he runs his patreon) appears to have a solid system going. New pages are not as accessible as far as a timely manner is concerned, for the general public, but they do still eventually come out I think. He's very approachable and it's possible you could ask him for pointers.

I'm a new reader and I'm stupid in love with your writing/illustrations. The "Ask the Cast" segments were fantastic and I hope they'll come back.

Depending on how regularly you start to produce pages, if you do decide to do a delay you could work that delay up slowly (if you post every week on patreon post every week and 2 days here until you produce the desired delay.)
Also, some of us just want to support you, but the buying Tobar an apple thing requires some of us to convert currency which not all of us can do.

I think, if you just want to use it as sustain, a single tier can be enough.

If you make various tiers, with different rewards, I'd say they should be shown to everyone too if they relate to the story, otherwise people might miss cool pieces: so I think the best thing to make everything still accessible is the possibility to make requests related to the story. Something I have seen some artists doing, and I enjoyed a lot, is the "readers questions" answered with sketches: people can ask things about characters, the setting, or even things directly to the cast, and the answers come in the form of quick sketches. Maybe only patrons can ask, or maybe they get priority on the answers, depends on what you feel. Like this for example: http://www.skindeepcomic.com/reader.....-question-101/

I haven't read all the comments so hopefully this idea wasn't already suggested! It could be neat to have more of those ask-the-cast things, or possibly even little side stories to accompany the main one (like how anime has OVA). Higher tier patrons could be allowed to vote on which characters will be answering the next round of questions or which character's side story they want to see next.

I like how people get to talking about each new page and wouldn't want to see different release timings get in the way of that, but of course it isn't my decision.