As it is, this game doesn't feel like D&D to me. Some of my frustration is probably borne out of the fact that I only came into EA just before Patch 3, so when they say that they tried 5e rules as they were and found it was necessary to change them, I don't know how genuine that initial effort was. It seems likely that many of the things that they're claiming don't work were problematic due to poor implementation and they gave up too quickly. If your first attempt at a car has square wheels, of course no one is going to enjoy the ride.

One of the biggest things that I look for in a good D&D game (and game in general) is the opportunity to develop a unique character. I want the choices that I make for my character to make that character feel special. My class, for example, should make me an expert (in training) at something that almost no one else can do well and most people can't do at all. The places where Larian has decided to deviate from 5e seem to almost universally take away from the uniqueness of the classes.
-Everyone can dash and hide and disengage equally well. Sorry rogues.
-Everyone can do unreasonable amounts of damage and elemental effects with barrels that they shouldn't be able to carry around and spell scrolls and grenades and special arrows that seem to be everywhere. Sorry spellcasters.
-Everyone can get all of their spell slots and other limited abilities back whenever they want, outside of battle, by long resting with no consequences. Sorry warlocks, monks, fighters, etc.
-Anyone can resurrect another character with ubiquitous resurrection scrolls. Everyone has access to nearly limitless, cheap healing by eating food. Sorry clerics.
-Reactions either need to be prepared in advance (and thus, aren't reactions anymore) or happen without your say-so. Sorry counterspell, feather fall, opportunity attacks, hellish rebuke, etc.
-Many class features are inexplicably more difficult to use than they should be, and so are less appealing. Sorry bless, battle master maneuvers, sneak attack, etc.
-The maximum range on everything is now 60'. Sorry longbows, heavy crossbows, long-range spells.
-It's relatively easy for anyone to get advantage on attacks. Sorry to all classes that have features that help them get advantage on attacks.

I'm sure I'm missing a ton of things that could go on this list and I imagine that there are good reasons for a few of these choices, but the pattern I'm seeing is that Larian doesn't think that the things that make characters special in D&D are fun enough, so they're changing things to make them all obsolete. I'm fine if they want to deviate from 5e rules, but only if they're doing things that actually make the game better.