Good point about D&D changing over time. I just think there's too many great RPGs out there to spend a lot of time hacking 5e into a system one is happy with instead of trying a different game entirely.
It's more that that the design goals of D&D don't match what I want out of a game and I don't see these design goals changing as they are doing very well by WotC; I've found other games that are more to my liking.
I don't like D&D 5e in general, partly because of issues outlined here, so I don't play it. I also don't care about any future D&D 6e. It's staggering to me how attached people are to playing an rpg that says Dungeons and Dragons on the cover.
I have found Hackmaster 5e to be a refreshing take on D&D. A simple orc is stronger than a level 1 character and larger monsters like ogres can be truly terrifying. In general, the default setting is lowish magic with a heavy emphasis on verisimilitude.
If you want this level of granularity, find a fantasy rpg that's not D&D. IMO the original monk is very much in line with the design goals of 5e, as such it is good as is.
The only thing that would be too far for me would be actually using the D&D 5e rules for my fantasy adventure game as I am not a fan of that system for a number of reasons.
My personal favorite F20 game is Hackmaster 5e. It may or may not be what you're looking for as it's pretty dense, but in my opinion it's one of the best higher crunch game systems out there.