Geeez, why ask me? I don't do cyclocross. But that lack of experience and knowledge has never stopped me before.... I'd go one of the STI variants -- brake and change gear at the same time. But then you'd probably want V-brakes, so you'd need travel agents to make the levers work properly. Although you could look at the Avid (?) brake levers.

Cyclocross bikes are pretty good for utility cycling, as I understand it.

Go to the cyclocross forum here? I'm sure they'd have more than enough answers for your questions.

(<sigh> It only took one question to really find me out ... that I'm just an idiot <shrug>).