Without going back to the sites I looked at, I know one thing I thought about was maintenence -- I'll be taking a bike maintenance class at my local shop, but I'll be starting from almost zero knowledge
If you start with a bike in good condition, everything adjusted and tuned to perfection, then you can almost forget about working on the bike during a summer long trip. Barring any accidents. Riding a bike does not cause a bike to stop working. If a bike works, it will keep working while you use it. Oddly, not using a bike might cause it to stop working quicker than using it. So start with a bike in good working order, and it will work OK for a tour. I ride every week with people who do not work on their own bikes, they take them to bike shop mechanics, and they do fine. Being a bike mechanic is not required to ride a bike.