There are a shitton of reasons that Wildstar flopped. terrible itemisation, broken PvP for a very long time, bugs, multiple exploits (medic DPS anyone?), very small and perhaps overly punishing end game, repeatedly missing their own patch deadlines and repeated releasing bug filled patches. Did I mention the problems with the end game? The added a daily quest type system for end game but it really should have been there at launch.
There also should have been more than 4 dungeons at launch. Even after these years I think there are still only 5 or 6 dungeons. If they released more dungeons more frequently I'd definitely go back to it. Hands down the most fun I've ever had in an MMO.
Anyway, back on topic. Does anyone see a problem with introsycing a mental of opportunity system in WoW?