What I really really really hate is when the mouse bumps against the corner of my keyboard, which is just at the right height to click the left mouse button. (We use giant keyboards like this at work, so they take up a lot of desk space.)
It’s within a few centimeters, unless you have the sensitivity on granny-level.
I’m not going to criticize wireless mice because I’ve never used one, and because I’ve heard they’ve improved a great deal. You didn’t mention if you game. If you’re not gaming, you’re not going to notice anything but the most egregious lag. People who game, especially competitive FPS gamers, will notice smaller amounts of lag than someone who only uses it for desktop tasks.
Wow. Is it that big of a hardship? I’m a, “touch-mouser.” I can reach out and find my mouse quickly and easily without looking at it, or even giving it any thought.