Looking at your list I'd be inclined to add an additional set of riding clothes so you don't have to wash them as often and are better able to handle consecutive days of wet weather. OTOH, I'd be inclined to cut down on the electronics and on some of the redundancy (filtration plus steripen plus tablets - won't you be likely to have potable water throughout the trip?; 2 flashlights + bike light?).

I probably wouldn't bother carrying a spare tire. So far I've always been able to patch/boot a tire well enough to make it to the nearest place that carries a serviceable replacement. I'd also see if the road tires wouldn't be sufficient for the offroad riding you plan to do early in the trip (but then I also take my crit race bike on single track from time to time).

BTW, I used a marker pen to indicate levels in the Oricasa bowl at 0.5 cup intervals - it's sometimes handy to have a second measuring cup.