Things I would make sure are good. Radiator, hoses, belt, water pump, steering pump, alternator, starter and brakes. All of those can fail with out warning. Check oil/trans fluid regularly during your trip. Take a set of metric wrenches, sockets, channel locks, and screwdrivers. all of the things I mentioned can be fixed on the road pretty easy. How's your karma ?
How often do you check the things you mentioned between normal oil changes? Do you always carry a set of tools on your vehicle? Like I wrote, a properly maintained vehicle will really not break down any easier than a newer one.
It sure is a good idea to check certain things before going on a long road trip and do occasional checks during it, but holy crap, you're not trying to drive around the world in rough terrain..