Glad to hear you were able to find a Surly Troll fork. Looks great with the bike! I stuck with the original components for my drivetrain, but will likely end up going 1x10 or 11 at some point in the future. Seems like a good way to go if you have the funds or the parts already on hand.
I'm running 2.1" tires on mine at the moment, but as you said, there's plenty of room to go larger. I reckon I could probably squeeze a set of 2.5" tires in mine. What size do you plan on running?
Not the best photo, but here's my current setup for comparison:
Photo Feb 24, 3 01 41 PM by
Dillon Driscoll, on Flickr