Not true about the fetch quests. Look at the rewards. Unless you need the reward now, you have plenty of time. A fair amount of equipment is in chests.
I just took every quest and explored for chests and fetch thingies. The fetch thingies appear after you take the quest. Eventually yes you will be forced to make a trip just to get something. However, you will be able collect multiple stuff.
If you do not bother talking to the quest givers at the first opportunity, then you do end up doing lots of back tracking. Start all the quests. Attack every enemy weaker than you. Search for fetch thingies as you travel.
GoldenSun/Crossbone Isle diagrams/ 18 teams known https://photobucket.com/u/SwordOfWheat/a/9990a2ee-25f3-4242-ae79-7d2d4b882be4