DISCLAIMER: -Thresholds are for acceleration, NOT sensitivity. -Deadzones are for sensitivity, NOT acceleration. Having a higher threshold means your acceleration will kick in with less thumbstick movement. Having a higher deadzone means your sensitivity will kick in with less thumbstick movement. Sorry for accidentally saying it backwards, but anyway I hope it doesn't cause too much confusion!
My reload is right bumper and melee is B, I'm thinking about switching them cause meleeing has become a pain, and reloading typically I reload in cover or die
I would definitely switch places with them. If you make your right bumper melee, that will allow you to melee while moving (which is extremely important in close quarters). As for reloading, I would keep it on the button pad (a, b, x, y), as you typically don't need to reload while staying in motion. I would keep the tactic of reloading in cover or when switching to another position, because that's what most people do (even the pros). Other than that, if you want completely seamless gameplay with no stops between reloading or meleeing, then I suggest you check out my claw grip video. It's definitely harder to master but it pays off in competitive gameplay. You don't have to use claw grip if you don't want to, however I would definitely switch that reload to the button pad.