The melee changes in my mind are absolute unnecessary "optimization for the sake of optimization," brought in because it sounded like a good idea on paper and nobody put more thought into it beyond that. There was nothing wrong with having the separate melee modes and now people who primarily were fans of the quick melee system are forced to use the clunky, awkward movesets that are associated with the stances.
In a single sweep they've destroyed the appeal of dozens of weapons and inadvertently encouraged the spin-2-win play style again because that is the swiftest and most effective way of attacking with a large number of them now. Playing on controller is an awful experience, so much of these changes were done with the excuse that it improved the "flow" of combat but I am constantly finding myself having to hit the weapon swap button so that I can go back to aim gliding.
This was a massive swing and miss in my books and the very least that could be done is give players the option to return to the old control scheme. We want MORE choices, not less.