making bosses better, how could it be done?

I actually really like the idea of a dodge skill variant for certain classes. I hate that all classes are slowly becoming these neutral masses of skills which are only discerned by their shapes and colors. RED is a step in the right direction, but they'll need to overhaul all the other classes to make them unique again. That, to me, is step one of making bosses fun.

Step two would be making bosses different as well. Root Abyss is a great set up. I love it. I even like Magnus, and Hilla to some extent. I want bosses which require thought and maneuvering.