I look at the smaller trips as a test run of the larger. Obviously, no trip will quite replicate a 3,000 mile ride through Canada and Alaska, except the ride itself. But, we prepare for what we know and attempt to prep for what we don't.
1. Tools - what to bring? What can logically be resolved on the side of the road?
2. Parts - spark plugs, tire repair, zip ties and duct tape ;). And my trusty aaa card (plus mc coverage)
3. Gps - garmin zumo 350LM
4. Rain gear!
There are other things that make the list...but those are the top needs as of right now.