The most underutilized characters?

Tesman85

I completed the quest Taste of Fear for the second or third time yesterday, and liked it as much as at the first time. Why? Because of the spooky plot partly, but mainly because of the characters. Silurie, Lindafwe and Hyircil were surprisingly extensively written NPCs for such a shortish quest. They had, well, character and were very likable. It was just fun to do that quest with those particular NPCs, since they were so personable. Because of that I remember that first time around I thought they would make a reappearance during the Summerset questline or something like that, much like e.g. Captain Rana pops up in a few places during the Pact questline. But after doing the quest - almost nothing. You can chat with them in the palace when the questline is over, but they won't appear during the Summerset plot, nor do they have any additional one-off quests. This seems such a waste of good characters, especially Silurie. Her backstory would be just perfect for her to be a Lady Laurent- like recurring standby with whom the player could have all kinds of wacky monster-hunt quests all over Tamriel.

There are others, too (e.g. for another Summerset example, Jurisreeve Lorne), but these three stick to my mind as the most badly wasted potential. I'm sure everyone has their own candidates for underutilized characters, though, seeing how many NPCs there are in the game. I'd be interested in hearing what NPCs others would like to see used more extensively and why.