I really like the idea of making boss "different" rather than just tougher. Sure, they usually have extra powers, but right now it seems their only real difference is extra resistance and hit points, making combat with them mostly time consuming and, given their drop rate, usually not worth the hassle.
The mission, and difficulty of the boss, should scale with the group size entering. Not all should be soloable, but the majority should. Too many trends of late force group play. I enjoy both, but enjoy the choice the most.
