Since you say you're spending very little time in the drops, have you considered some style of flat bar? I changed all my bicycles to flat bars, either flat MTB bars or an inch or three of rise via a BMX-style bar. I get a little more width to the bars (better control, IIRC) and my old body likes the little extra height; the bars are about 54cm wide. You'll need new brake levers and shifters (minimum) along with handle bars and hand grips. If you're going to change you might as well consider all the options.