You're correct in wanting to have the adjustments somewhere close to the middle, but that's not always possible without shimming something or using an angled base. Seems to me that higher rings would just put it farther off.
DropShot: just to add to what Pappy said, Burris Signature Zee rings (with the insert) will allow you to make considerable adjustments to the rings themselves, then fine tune with the scope adjustments themselves. Just a thought.
RM