It's nice to see your reply, I don't mind reading long responses!
Sorry I just assumed that was procrastination. Now it makes sense that if you have a more polished UI if it was re-used from previous projects. If you are new to gamedev, welcome! 3D is truly a beast and I respect your attempt at it. I dabbled for a bit in 3D then never got into it after learning about all the complexities :D But I do want to get back at it some day
Yeah, collaboration is very tricky. Experience varies from people to people. But if you do it right, you may create games that you would have never created by your own. It might be easier if you start collaborating with someone you know on a short limited term, just my 2 cents.
I wonder what made you think working with a 3D artist made you unpleasant though?