For what it's worth, I race with a single 38t chainring and a 12-28, 9 speed cassette with bar-end shifters. This works well for my purposes, though the bar-end shifters are sometimes hard to grab on bumpy courses, and it's really tricky trying to shift when you're out of the saddle. The advantage of them is that they work flawlessy in really crappy conditions, and they don't break when you crash. Eliminating the front derailleur with the single ring setup removes one more mechanical liability. A singlespeed setup would be even more reliable.
As for riding position, I use the hoods for climbing, the drops for sprinting, and the tops for everything else. I use cyclocross levers on the tops. I also reversed my brake controls, so the left brake lever operates the rear brake. This is useful for high-speed dismounts, where you typically dismount on the left side. Reversing the levers allows you to slow the bike without locking up the front wheel while approaching an obstacle.