Finding an L/R in another controller that you like doesn't really do much.
The actual plastic button doesn't matter at all unless its really ****ing dirty or the controller shell is really ****ing dirty. Or the plastic is warped somehow, in which case you need to replace it. Just clean it.
The spring will barely matter for your needs. Just clean it. There is some pressure adjustment stuff you can do, but it doesn't really make a difference unless you have the hands of a 3 year old girl. Just clean it.
The rubber button that the plastic piece pushes into the 2D dildo-shaped piece of board matters if you want to change how hard it is to press the analog button (powershielding, air dodging). There are a wide variety of ways to adjust this, but most of them are irreversible and you will probably **** up a handful of them before you get it the way you want it. Just clean it.
The slide component that is connected to the motherboard that registers how far you have the plastic button pushed down (lightshielding stuff) matters a lot. Most of the controllers I've had to fix that had sticking issues had issues with the slide. The plastic rubs against the inside for too long and becomes rough, the thing gets clogged up with dirt or something, etc etc. Clean that **** out. Lube it up with something that is plastic safe (I recommend the kind designed for Rubik's Cubes). The friction caused by that slide can make it harder to slide the L up and down, and can make it take longer to go back up after pressing it down, which causes the infamous: "My L/R sticks after I L-cancel or wavedash and my shield will stay up" problem.
So, to summarize:
1. Plastic Button - Clean it.
2. Spring - Clean it.
3. Rubber Button - Clean it.
**************4. Plastic Slide - Clean it and lube it. **************
Note: I put "**************" there because that is the important item. In case you didn't notice.
Bonus: If you open your controller and your L/R has a shield screwed on top of it and/or a metal hinge/clip thing to control the motion of the plastic button... take that **** out. Completely unnecessary.
Edit: Inb4"ohthatswhyhesummonedcactus"
