I'm going to be pretty controversial here... but what I would like is...
No boss fights.
Yes, I went there. Arbitrary boss fights have always been a weak point in RPG's, and I dare you to find a fight that isn't complained about. Having to stick all challenge into one foe also really harms the possibilities of what you could do. Most then compensate that with "adds" but that's generally just a done-to-death miserable sollution that usually doesn't solve the issue.
So yeah, no bosses, just... encounters. Some of them stronger than others, but not specifically set up as bulle... ehm... sword-sponges.
For example the battle on the Graveyard with the Skeleton King and his follower was much more fun that the end-battle of Ceseal (did I remember it correct?) with just this large HP-bloated guy who send in his adds which could actually not join the combat.
Overall I can't say big boss-battles have been D:OS strongpoint, just look at the complains at the final battle, or the "season king" section etc.
So rather than spicing them up with cutscenes (which wont solve the underlying issue) I would be more for removing them and keep the cutscenes for other impressive moments. A fly-over of a bay you look at. An earthquake happening. A dragon fly-over. Anything.
Just my 2 cents.
