When's the last time you didn't find a Kin of Tarasque or some other high-level adventurer prof instruction disc or nano on the corpse of some lame level 180+ mission boss?!
There's very little motivation to kill high level mission bosses simply because the loot (and XP) reward is not worth the effort, in most cases (except for those rare times that a high QL Albrecht Tank armor or CHS drops).
I want to see a greater variety of items and nanos drop from high level bosses, even if that means those items have to drop in lower QL versions. I mean, wouldn't it be nice to find even the lowly GA MK I on a ql 180+ boss? Or PPPEs? Low QL concrete cushions? It would bring a refreshing change to the monotonous predictability of knowing 50% of what the typical boss's drop is going to be.
You know what one of the big problems with this game is? Yup. You guessed it. Predictability.