It's not adding buttons, it's changing the placement so you no longer use the face buttons and 2 options on the d-pad. Placing jump on LB instead of comfortably on the back of the controller sounds like hell, and what are you using for grenade and ice bomb?
LB for jump is by far the best jump bind. it's easy to reach.
LB = Jump
LT = Secondary Fire
RB = Grenades
RT = Fire
the rest of the buttons don't need precision as the chainsaw is basically auto targeting and the flamethrower has a gigantic cone. and you can map that to B which on an Xbox controller can be easily pressed with your streched out index finger.
the issue is, as soon as you get used to controllers with paddles/back buttons you need them for every console and all with similar layouts.
as someone who plays on all consoles that's simply not a viable option.
so Bumper Jumper is the most consistent layout to use with slight variations depending on game.
also, to me nothing feels worse than back buttons/paddles. I have a Razer and an Xbox Elite 1 and 2, and dislike using them on all of them... I also have a Hori Split Pad, which is even worse due to bad ergonomics on the grips compared to normal controllers.
so LB it is for someone like me who plays shooters on like 3 different consoles, sometimes in the span of a single day.
the only time I ever use back buttons is when a game has absolutely atrocious button layouts with little to no customisation, example Halo 5, where there literally exist ZERO decent layouts and you can't remap freely, so I had to map Melee to a paddle in that