What's your programming experience? I'm curious whether Ren'Py is your first language or that you've programmed before!
A few pieces of advice in general:
- AI is very convenient, but use in moderation (I know how hypocritical this sounds XD). It's a force multiplier that saves a lot of time if you have a bit of experience, but while you're learning it may hamper your ability to learn if you only consider "does this code work or not" and not "do I fully understand what the AI is doing in this piece of code".
- Feature creep is the enemy. You'll have thousands of ideas that you want to implement, and only time for a hundred at most.
- If you're not having fun anymore, you won't finish. Slow and steady wins the race,
- I don't know if you're planning on having AI artwork or are going to make renders, but if you're using AI: creating LoRAs is easy and does wonders for character consistency.
Have you played the Ren'Py tutorial that's included in the SDK? That basically contains 95% of what you need for a first game.