To be honest I'd prefer something more blizzard*, I know - I'm an awful person, but I'd rather see something I can fiddle with easily than something that will probably compound punishment for poor choices. Besides the obvious "Meritlvl10 or kick" for some content I can't imagine trying to be a tank in the first level 60 dungeons as a fresh 60 and playing with completely decked ilvl250s full merit allocation, it'd be insane lol. So I'd like to see customization but I'm not particularly excited about a merit system for that.

*While yes there is WoW and their tree I was actually thinking more Diablo 3, a lot went wrong but being able to make a build without seppuku was nice imo. They made you live with your build during combat but beyond that just switch out whatever wasn't working for your style or team.