There's only 4 classes, reskinned as a lot more. The power system means there's very little you can do magic wise out of combat, and with how the powers were daily/encounter/at will, if you didn't resolve combat by dumping your big powers you were in for a slog of "I use this at will attack again", every round, at every level. All the powers gave a ton of tiny random bonuses that were such a pain to keep track of it led to the creation of advantage and disadvantage. All the at will powers are "I attack and another small bonus thing happens", so if you want the bonus thing but no enemies are in range, guess what, you're attacking the wall/the ground/whatever. Honestly just a miserable time for the most part. What it had going for it was that it was incredibly simple to pick up, because all the classes worked exactly the same. It also simplified 3.5e's cool but overly complicated skills