I remember Weasyl but I don't remember it being too active. Has it gotten better?
Also wasn't toyhouse invite code only? I think I have a friend who might have a spare one though.

Weasyl, Inkbunny, and Pixiv come to mind when it comes to active sites.

(Also, what are your internet speeds to have Tumblr lag out on you?)

Internet struggles to give a solid 2 mbp. My service went to hell when Verizon got bought out and my current tells us we can't get anything more than 3 (be nice if we even got that). Between busy schedules the person who needs to call about canceling and picking a new service hasn't had a chance to do so.

I tried Inkbunny for a bit but the amount of untagged babyfur made it hard to wanna go check on stuff.
I'll look into Pixiv though since I'd like to see how their anthro/furry community is.