Standart roguelikes are games for far more than 1.5-3 hours as DooMRL. You often think a lot there on every your move, check your inventory and stats often. It's ok to use keys from all over the keyboard, to spend more than 5 secs on every move. DooMRL is more like original DooM in this question(at least for me), it's possible to play it fast(or at least faster than other roguelikes).
not to mention you actually change only wait, unload, run and messages bindings
It's very uncomfortable if you have room filled with pistols, and you need to unload them, to get to the one of them, press "shift" with your left had, draw right hand from numpad to "U" letter, type it, then draw right hand back to numpad, go to the next pistol, then again draw it back, and so on. I wasn't using "run" untill i changed it from "," to "a" because "a" is near fire, so you always can tap it quickly. Same with wait. And messages - they are "M"essages, there isn't any "P" at all.))
... hardly a huge change.
Let's change fire from "f" to "&", it's hardly a huge change too, but it becomes VERY uncomfortable to play.