So let's have an original quest idea that isn't a fetch quest. Let's see what you come up with. Maybe something for the Fallow Mire. That zone could use more development.
Me, if I were going to design a quest for the Fallow Mire, I'd have the party look into the plague. Yes, collect tissue samples, but then you'd have to take them to an expert in Val Royeaux for analysis. There would be two experts available, one who would do your research for free and one who would charge a hefty amount of coin. If you chose the free one, they would determine that the plague was caused by the Avvar polluting the water with dead goats. Since this quest would only become available after the Fereldan soldiers were rescued, you'd have to go to a settlement in the Fallow Mire and negotiate with the Avaar to get them to stop doing that. They would explain that its a sacrificial offering to appease the hungry god of the marsh and that they aren't about to stop doing that. At that point, you could attempt to prove to them that there is no hungry marsh god, but it wouldn't work, and you'd probably wind up having to fight someone. The more expensive expert would determine that the poison causing the plague was manufactured locally, perhaps as an experiment gone wrong. You'd have to go from building to building collecting clues (gasp, more fetch quests!) that would indicate dealings with an apostate. Eventually, you'd gain access to the mill on the eastern edge of the map, where you'd find an apostate who accidentally caused the plague. He's now working on a cure, but he needs help. You'd have to go to a few other Act 2 places (Exalted Plains, Emerald Graves, Forbidden Oasis), where you would have to convince other mages to part with their research. Once either path was successful, villagers would begin returning to the Fallow Mire. You'd get a lot more loot and experience by going to the more expensive sage.
Mind you, the whole quest idea contains a lot of fetch quests, so it would probably still be unsatisfactory. But ultimately, everything is a fetch quest, isn't it?