I will like the targeting system once they fix the pets related macros. You can target, not just next mobile. But next enemy, next friendly, next party member, etc. And then macro whatever your attack combo is. Or heals.
I do not mind the graphics, except that when your deocrating your house, it ends up with a different 'feel' than what you intended in 2D. And your character in game looks like a lego man.
Biggest gripe is the map. Siege depends on group coordination which we have with UOAM. They need something like that in KR. And it needs to either coordinate with UOAM, or also be integrated with 2D. Folks like me cannot fully integrate KR until we can coordinate with those still in 2D.
Lag...I lagged on my 2 year old laptop that could play WoW, DDO and LotRO fairly well. On my brand new desktop, no lag. What this means is even if folks want to try it, unless they have top of the line machines, they will not becasue why switch if your current game runs faster. Choose to die to PKs? I think not.
And again, until it is playable by the majority, those of us that would like to try it, can't becasue we need to coordinate with our mates.