There are so many more elegant D20 systems that could still be compatible with D&D...
Cypher System (from Numenara, Monte Cook games pnp) gameplay involves a simple die roll to determines success or failure in any kind of action. The GM assigns a difficulty on a scale of 1 to 10 FOR EVERYTHING—a 1 is extremely simple, while a 10 represents a herculean task beyond the means of most mortals.
Once the GM has assigned this difficulty, the rest is up to the players.
Players apply their skills and experience, tools or other advantages, aid from one another, and other assets to reduce this difficulty. They can also focus a limited resource called Effort to further lower the difficulty of actions really important to them.
Once a player has reduced the difficulty as much as they are able, they roll a d20. The target number is equal to three times the difficulty.
This system resolves EVERY TASK, including combat. Creatures and NPCs have levels, and an opponent’s level is the difficulty of any task it opposes.
In combat, for example, an opponent’s level determines the difficulty to attack it, and to defend against its attacks. (Or anything else for that matter—tricking it, talking it into something, seeing through its deceptions, and so on.) That doesn’t mean opponents are necessarily one-dimensional: A level 3 creature might make attacks with its fire whip as though it was level 5, but defend against mental attacks as if it was level 2. The design focus, though, is on a creature’s motivations, tactics, and interesting abilities, rather than a large block of statistical information. This frees the GM’s attention to focus on using creatures, story elements, the game environment, and so on in a creative manner, rather than on modifiers and numerical details.
In short, the Cypher System’s game engine elegantly keeps the focus on story and action, without sacrificing structure or mechanical detail.
I know this isn’t the point OP is trying to make, but I don’t think the problems are the dice mechanics of 5E, but rather how Larian is surfacing them to the player. Agreed, many players could care less about what’s happening under the hood – but that’s exactly what makes this game special and should be leveraged. The popularity of 5E speaks for itself.
