Is this okay... (worried in a bad way)

I've seen apps before that let you do this much for free with no ads, but they ended up not lasting. Eventually, the free service quality dropped, users left, and the service shut down. If you make the free tier too good, more users will stick to free instead of upgrading to paid, increasing server load. To cope, they'll start limiting free users. Then, free users won't move to paid; they'll just leave. That's what worries me. It seems like you can even rewrite prompts for free, and setting up various developments with the same character is great, but I think 'sustainability' is crucial in system design. The subscription price also feels a bit high, which is another concern. It's like a narrow entrance with a huge lobby in front of it. I have a feeling it'll become a service where everyone just hangs out in the lobby before the entrance.