I'm going to offer some advice to cope with vertical difficulty spike.
1) check psn profiles guide for easy leveling trick (I'd recommend trying other things before that)
2) check Customization guide. The game doesn't give you good weapons, in fact you're stuck with garbage for the entire game if you don't use it!
3) blacksmithing (same thing, if you don't get good armor, you're fucked)
If not for awful PA system, arena, backtracking and difficulty spikes it'd be a great game