About changing the default characters:
I'm against it. When a new person sees those first default characters, he says "wtf?" and it compels him to look and see what other depraved imagery is in the offering. Stick figures could well serve to quell any curiosity whatsoever from the start.
About subscription:
I'm of two minds about this. I would pay a small subscription fee to stay here, but I'd hate to lose some of the people who might not simply because of monetary concerns. Still, I'd hate for you to have to pull the project eventually because it's too costly.
Maybe you could do a donation drive a couple times a year, and offer a "friends of stripcreator" designation to people who offer so much, and other levels to people who donate so much more... etc. Then they'd get an image on their comics page that shows that they donate to help the site out. People are vain. They like that kind of thing.
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I am a delicate fucking flower.
https://beacons.ai/jesskent