I tries kill final boss on maxed about hour, and can't. I think i leave him with 20-15%HP(Based on cheated kill shots and one time I get intensive fog but can't finish him) but can't... May be I too tired, but I think it's not too easy even on first difficulty. (Relative to first level and some other places that i tries fast-pass on visitor)
I think easiest levels can have more behavior nerfs for bosses and mob-jumping.
For dominator, hmm i think it feels enough at avg. but have non-linear curve for some levels/parts. But with my playstyle i am not so good sample to balance difficulty.
Damn! I can't beat him for more than hour... It's really long with even hard bosses for me(At shooters or platformers, I almost don't play in dark souls (: ), but may be I just not recovered enough from sickness and slightly tired today.