While Psychic powers were always planned, the Devs couldn't agree on what exactly they should be or how to implement them until very late, so it doesn't have as much unique content. It's still perfectly playable, especially after Fenoxo (the lead Developer) did a playthrough and tuned up some of the abilities.
Class-specific content isn't all that common to begin with. A lot of equipment seems to have been designed for specific classes, but there's nothing stopping you from using gear on the 'wrong' class.
If you feel you took the wrong Perk, you can refund it if the
Cheat Menu is active.
You can't refund Stat points, but it's possible to max out all stats with
Stat Training.
If you have more specific questions, feel free to ask.
