I am not blessed with long fingers, yet have no trouble operating the original-GI-dimension parts, whether shooting righty or lefty. (Yes, that does include the selector lever; I do not like ambidextrous selectors, even when shooting lefty.) Every extended part, that I have tried on an AR15, has gotten in my way, in some annoying way. My first AR15, a Colt AR15A2 Govt Carbine, had some of these doodads, but I sold it to an LE colleague with younger eyes, to use as his patrol rifle. Other than one of my several AR lowers having a slightly oversized “ping pong paddle,” and all of them having somewhat extended extended charging handles, I use AR15/M4 rifles and carbines with normal-dimension controls.
Notably, however, I do not shoot competitively. My standard has always been, “What do I want, on the weapon, if I have to rush through a SE Texas thicket, in the dark?” We have big thickets, down here, in this wet, green part of Texas. Others’ needs may vary.
I do not claim to be any kind of expert.