I'd certainly like to see difficulty not equating to just damage and 'health' and I would like the Ai things you mentioned but I think that before that, there could be some more tactical behaviours that come in to play in more difficult activities. I did think about this a little when people were talking about pvp and pve sandbox balance, and I concluded that the reason for wanting different balances was because pvp enemies barely ever behave like anything other than total noobs with slightly different personalities. There are things I like, which I think would improve the game if they were built upon further, like the difference between how the different races behave (dregs hiding compared to goblins teleporting to cover then attacking for example) and different unit types behaving in a way befitting a role (e.g. vandals 'sniping' at you from a distance but changing attack once you get closer) I'd just like that type of mechanic to scale with difficulty. I think maybe what I'd like is more tactical behaviour across the group of enemies as difficulty increases, maybe even with some system where command type units enable the tactics, giving an incentive to take out the commander(s) to make the group lose cohesion, I'd love that to be more intelligent in some way but accept that behaviour adaptation is limited by the platform capabilities as has been mentioned already i think. Despite this, I still think there's room for improvement between here and the limits of possibility. A few preprogrammed strategies that trigger randomly, or even better, based on your class/subclass/group makeup (or could be a unique part of a strike/raid), would be a good way to add some more depth to the challenge and variety of a lot of endgame activities in my opinion. I'm sure other things would need some balancing as a result, but personally I'd prefer enemies that aren't tanks, but work together. The Heroic Mercury missions would be my example of something I dont find appealing because it seems like a mindless 'keep shooting the bullet sponge' activity, especially Solo. Heroic adventures seem like they should be a challenging endgame activity that can be enjoyed solo, because they're parts of the campaign, but harder. That's my 2 cents anyway.