Tanks has had their aggro generation insanely buffed so they could concentrate more on DPS. Back in heavensward/ARR it was alot harder to maintain aggro.
Bard/Machinist casting has been removed so they can continue moving and dpsing more easily.
These things happened due to player feedback and the players are now asking for removal of positionals for reason already stated in this thread.

I am in support of removal of positionals particularly for Viper.