Losing covenants with no real replacement. Most enjoyable form of diversity the game has ever implemented, unless you’re playing >gladiator or mythic raiding week 2 you always had a choice between multiple covenants which for some classes completely changed your synergy with others. But yeah, the community is selfish number crunchers who don’t even understand the calculations beyond what some guy wrote a simulation for… they complain about PI for christs sake.
I preordered twice however, wanted to mess around with two boosts on characters I heavily dislike the leveling process for.