Use discretion, don't accept everyone/anyone's request. Only the ones you like most/the ones you feel like you'd have the most fun drawing.

Alternate streams, and make sure people know what sort it is. It'll suck at the beginning, but each person you're helping out will offset each person who bitches about "But you're a free artist... WHY CAN'T YOU BE FREE" while you and the stream gets used to it.
If nothing else, put a donation widget somewhere to encourage a little bit of aid from the peeps who're there.

There's no easy way to monetise your content. It's just about adding as much sugar to offset the salt as possible.

Have a queue. Or just raffles. Like do like 1 or 2 raffle streams for those who come to your streams. Then the rest of the times, it's only commissions.

I'm confused since this is the first I've heard of this kind of thing. How do you lose commissioners whether or not you have people pay to see the streams?

And does not getting to see a stream mean that they can't have a commission?

Generally people will see free stuff and will postpone purchasing art, thus preventing money.

My Personal Parameters.
includes most or all of these things per freebie session.

1. Always have a cut off, no exceptions. Ex: 5 Slot freebie
2. Repetition/Thematic, Have a theme Ex: Females only, Scalies only
Repetition Ex: Waitress Butt Icons, These are my go to freebies.
3. Spread it out. Ex: Watcher Goals, Bi Monthly(recommendation from me), Personal/Public Holidays.
4. Use it to your advantage. Ex: Practicing X Species, Doing sketches! Head, Tail, ex...
5. Don't over kill. It usually shouldn't look like you spent hours on it/looks paid for.
6. Purchase Encouragement, Ex: Raffles that open extra numbers to past/current commissioners.

That's all I can think of atm.

Did like you did before. Have people pay money to ensure they get a slot to get art in a freebie stream. As for the other, choose whoever you feel like drawing when you're doing the freebie stream.

The best way to do that is to pick and choose who gets a freebie. Or have a set limit like 3 - 5.

Not matter what you do, there will always be a whiner in the crowd. Its just a live and learn thing

I'd do a randomizer - just so it's fair - even if a person can pay for it haha

why not make a paid lotto
$1 per person min to play the lotto (or $1 per ticket)
one person wins *shrugs*
I personally love you art and wouldnt mind doing this

One half paid, one half free. Everyone wins! owo

(Still trying to get the money for a paid one or a donation though. I know, I say this every time you stream but I've fallen on harsh times. :c )

Make one day dedicated to free art with chances to win and not confirmed free slots.

i tink maybe open up commissions regularly but when you feel like free arts, hold a raffle for those who may need arts like how you discribed. :) You can stream the raffle winner(s) pic if you want to. :)
I hope this may help a lil. :)