48 spoke phil woods laced to some tandem rims like Velocity Dyads would be my first choice if I were you, and then a Brooks Champion Flyer for cush.
I think it's all pretty basic but what do I know? You can get a touring crankset with steel chainrings for durability (forget the maker) and run an 8 speed instead of 9 in back because 8 speed is said to last longer.
I can't tell the diff between my XT and LX rear derailleurs except in finish and jockey wheels, but the XT front derailleur has an extra cable pivot for more leverage and smoother shifting compared to the LX.
Have fun with your LHT, I think you'll like it once you get it dialed in. One last thing - though not a build issue, but an extra- I just put a twin leg ESGE kickstand on my LHT, it fits without much hassle and will become indespensible on tours in the long run. I recommend it.