Lots of mine able coins are heavily pre mined by the devs so you have to watch for that. I think you have to trust the project and development team and decide if it is worth the risk. I'm not concerned on non mine able tokens if I believe in the project.
Yes really you need just to believe in project.
In my opinion good coins on etherium.
Etherum have great developers, and Buterin is computer genius.
So no matter mineable or non-mineable. Matter is developers!