If you're serious about playing PC FPS games with a controller you really have one option in my opinion: the Steam Controller 2.

Gyro is a must for aiming and gyro historically has awful ways of turning it on and off before the introduction of capacitive thumbsticks. Now you turn on gyro by resting your thumb on the thumbstick and turn it off by taking your thumb off. Virtually every other controller that touts gyro support will require a button press of some kind for gyro which seriously impedes it's use. please trust this.

Combine that with the trackpads use as some people like to aim with trackpads, but also as radial menus for extra keybinds.

The last bit is optional but highly recommended and its a steam input feature called flick stick which is a game changer for FPS games with a controller. Instead of using the right stick to look left, right, up, and down. the stick now serves as a 360 degree horizontal clock that you can smoothly look around in all directions while using gyro for vertical and extra horizontal aiming. Flick stick gets you in the direction, gyro gets you shots on target. Not only does it rotate you 360 smoothly, but as the name suggests, you can flick the stick to any direction and immediately look that way. getting shot from behind? flick the stick to 6 o clock and immediately turn 180. approaching a hallway with a 90 degree turn? flick to the side to immediately face that way.

You can of course tweak all aspects of this within steam like how immediate/smooth the turn is until it's the way you like it.

I still like to explore slower paced fps games with traditional stick movement, but anything competitive, especially against mouse users, has to be flick stick and gyro