I have lots of ideas in this brain of mine but I have a hard time getting started because of a lack of art (as in the ability to do it)
Sorry for being blunt, if you had the sprites can you start making the game with whatever engine you choose?
I have used some AI art to slightly bring my ideas to life but I feel that it's lacking the human touch.
Then don't use AI artwork if you don't feel like it.
I also think it would be cool to join a team to develop a game to just throw my ideas out there and see them possibly come to life.
Sorry again, you can't join a team, throw ideas and expect them to work on your ideas.
TLDR, you should draw sprites yourself and start making the game from scratch. It may not be easy start but trust me, the joy of creating your own game is worth the trouble ;D.