exactly my thoughts also....
i kinda like the dungeon, but i really don't go there often and my best is +9 in time, so i can't really talk about high lvl keys there. but this week i had the pleasure to run a bunch of it cuz i was helping boost my brother and few friends.....and ffs how lucky they were with those keys. we started with +2 KR and than ppl started to get +4, +6, +7....and since we were already there we did 4 in a row
and those little fear fukers with 1hp, especially the first huge group of 8 with a combo of Bursting is a interesting encounter :P
and also, if you get like 2 wipes, it becomes really hard to beat the timer so +2-3 mins would actually make a difference.