Sounds like a great place/s to tour.
I know what you mean with the muddy roads. About discs brakes, they are great but just a few things to keep in mind,
They don't like water, especially dirty water, dust, grit, mud nothing worse than a clogged or jammed caliper/piston. Replacement parts may be hard to come by, parts can be very specific. Discs can bend and can be a nightmare to fix on the go. Emergency repair / Maintanence can be more complicated sometimes impossible without some extra tools.
Unless you are doing some fast / downhill technical terrain where you need constant braking control it's may not be a necessity. A good set of disc brakes can set you back a few hundred more. Other than that I love them when they are working and totally loath them when they are not.
V brakes have less parts which means less can go wrong. parts much easier to come by.
Alot of makers have touring models with headshocks. These can easily fit paniers, have flat bars for bar ends etc..