Another vote for a rigid fork and canti brakes. V brakes are also good, but are more sensitive to wheel true. BB7s are good brakes also, and I keep intending to put them on a bike up front as a third brake. Brake failure up front is a scary proposition. The downside is the weight and the effect one your rack options.

You are using a 29er frame? That's an idea, overall I would think you would be better off with a touring frame. You really need two bikes. Once you want some fancy MTB with suspension, but want to go out there on an expedition touring bike, I think you have too many things pulling in different directions. No reason it can't happen, because almost anything that will mount a rack will work to a point. But when you are out there for weeks or months at a time the better ergo and function of a properly designed touring rig will probably be appreciated. Almost any one thing can be done by a given person, but that doesn't make it a good idea.

I really hate expedition bars, poor ergo for the most part, a kludge to get MTB semi comfortable compared to straight bars, which were really not designed for long term use. So what you get are two straight bars with a bendy bit that is hardly a grip. Break the major hand positions into idividual grips, none of them are great. Others don't agree which is fine. The thing is one rarely sees expedition bars on a normal bike, they aren't so superior they end up in the tour, yet drops hold their own on any bike with a modicum of versatility. From Dirt drops to racing bikes, messenger bikes.