I think what some people, especially those who view the level cap as something to race towards, forget is that while a long time vet who's ran a dungeon hundreds or thousands of times can clear most dungeons in 10 minutes, that's not true for someone who hasn't ran a quest before. Even when grouping, long quests can be cleared within minutes... But this is only possible if you run past practically everything in a race to fight the dungeon's boss.
The reason The Pit has always been such a hated dungeon is not because it's a hard quest. Rather, it's hated because it's a lengthy quest that you can't really race through. Nor can the party split up to accomplish multiple goals at once. Personally, I like the quest. Always have, really. But yeah, running back and forth in a confusingly laid out dungeon can be tedious. And for those who prefer to zerg every dungeon to get maximum XP per hour, being forced to slow down is their kryptonite. As I recall, you can't even memorize the rune wheel puzzles, because the solutions are randomized. And trying to brute force them takes too long, due to there being 5 or 6 rune wheels.
I've said it before, and I'll probably end up saying it again... Gamers are known for optimizing the fun out of their hobbies. Then they look around after racing towards their "the real game starts here" end goal, and realize there's nothing to really do now that they've reached "the real game". Personally, I've always thought the mentality of figuring out the fastest way power level to the level cap in any given MMO was silly. People who do that inevitably end up complaining that there is no content in the end-game, or not enough content. And they do so without understanding they raced right past the majority of the game's content.
Reaper XP and the "problems" surrounding it are the same, IMO. You have people who raced to 156 reaper enhancement points, for some reason thinking once they reached that point the real "Reaper" system would become available to them and they would be provided the challenge they say they want. Only to not realize in their rush to max out the Reaper trees, they were racing past the very challenges they were asking for, then expecting the system to still provide challenges. Same thing happened with reincarnation. There's a bonus for reincarnating from each class 3 times? People raced to do that as fast as possible, only to then complain that there's nothing to do but farm content they are now over powered for.