I suggest finding a comfortable setup. In my experience with ergonomics, a poor setup can hinder your abilities. You need an interface that feels like a comfortable, responsive extension of your body. That means calibrating your viewing distance, your posture on your couch, and your mouse or gamepad feel.
Sit at a distance where you can see every detail comfortably; sit in a way that holds up for a long session and lets you manipulate your gaming interface easily. Make sure your input device is sensitive. Gamepads historically came with dead zones that make them feel imprecise or laggy. If you use a gamepad, make sure it is precise enough to use as a mouse on your desktop (raw input, no deadzone, max sensitivity). If you use mouse and keyboard, make sure you are comfortable while being precise: that's the hardest part. If carpal tunnel is creeping in, change your posture.