Don’t buy the cheapest, but don’t buy the most expensive, look for a case that’s the right size, and easy to open, has a few fans, not too many but not too few. Cheaper cases have really thin metal that bends and cuts you.
Front panel matters, how the drives mount matters (less so now that we’re all m.2), honestly spend $70 on a decent but small case, you’ll be fine.
If you’re fine with atx go atx, smaller is harder for airflow, but not always if we’ll designed.
Size matters less nowadays again with m.2, the old optical and hard drives really made most of the constraints, now it’s all about your gpu and then your cpu cooling.