Great post by the OP! I was actually about to make a separate post about some of these issues (namely the disengage as a bonus action and backstab mechanics).
Admittedly, I am fine with a few liberties here and there regarding rules, as both Jeremy Crawford and Larian in previous interviews have mentioned that there need to be some changes for a video game vs. tabletop. However, I definitely have an issue with disengage being a bonus action, even if decoupled from jump, since it also takes away that tactical decision of whether I take an attack or get the Hells out of Dodge (which to me could still be a decision choice for melee characters low on health or trying to get closer to a healer). The way it currently works, even ranged characters can "jump/disengage" out of the threatened range and still get a shot in. My main issue with the current backstab mechanics in EA are that it's difficult for us to direct where our characters are facing at the end of the turn, so it's harder for the player characters to protect their backs and avoid a backstab than it seems to be for the NPC enemies.
