It really depends on your bike. Vintage bike with vintage drivetrain takes a lot more fiddling to keep things tuned. A new bike with mechanical disks and a rohloff wont need much except new chains and pads as they wear out. Either will do the job.

Its like my parents cars: my mom's VW turbodiesel can cruise 5-600 miles on a tank at 85 MPH day after day after day with just an oilchange every 10k miles. My dads 1971 vw campervan needs to stop and have the carbeurator adjusted if it climbs more than about 2000 feet. If you can cruise at 60 in the poptop, you know you have a tailwind, and you had better make sure you have an extra clutch cable before setting out far from home

As far as maintenanace, if you are setting off on a long tour, prevention will nip most things in the bud. Get a new chain, get some new pads, and maybe new tires for a long tour... if you buy or build well built wheels you wont have spokes breaking (most likely). If you take care to use split washers and stopnuts you wont lose bolts on bumpy roads. I like the self cleaning lubes, personally, since the dirt falls off, but these require more diligence with application...

Other than that, know how to split a chain, know how to properly adjust a headset or hub cones, and check bolts etc. periodically for tightness. Also, when you hear funny sounds that didnt used to be there, stop and figure out what they are. They wont go away until the part fails....