I centered my stick mainly because I switched to A10, but I must say I find it to be more comfortable than a sidestick. And yes, it does give more room for a mouse area, and it gives you the opportunity to squeeze in a stickshift too then, if you're into racing..
Btw, do you plan to play shooters and the like on your setup?
I find it to be a pain if I have to use the mouse for any extended period on my setup, and my mousepad looks to be in a similar low position. Cockpit-clicking and surfing is just fine.
Fortes Fortuna Juvat