You can install road brake levers on the forward part of the bars, moustache-bar style (you'll likely need a shim for the clamp, though). This gives you braking from the forward corners, and an extra hand position (hands resting on brake lever bodies).

Currently I have mine set up with old non-aero levers working as interrupters on the forward portion and four-finger mountain bike levers on the rear. For shifters, I'm using thumb shifters mounted under the bar next to the forward brake levers, which gives me instant access from the forward corners (where I do most of my shifting), and isn't much of a reach from the other positions. I also tried mounting them vertically on the outsides of the bars, which I liked except for the fact that it inteferred with the hand position there. It all looks crazy, but works pretty well.