Lots of issues here. Will break it down by section
•Floor 1
The goal is to kill enough enemies to unlock the seal for the 2nd floor as fast as possible. The fastest way is to AoE enemies repeatedly with the gravecallers reviving them. The issue is that if you don't do this it takes longer, but even if you do it there isn't a reward because the experience is close to nothing and the drops are unrewarding even if you kill the revived version of enemies.
•Floor 2
The goal is to free the captive exiles. Best thing to do is just morph and run past all enemies that aren't near a captive and only kill the ones guarding captives. Not sure what the point of the enemies are since you can just ignore almost all of them. Again, bad exp and drops.
•Floor 3
The goal is to destroy the three seals to spawn the barrier guardian. Same thing as previous floors, you run past almost all enemies besides the few at the seal wardens. These don't drop anything and give poor exp.
•Floor 4
This one actually encourages you to kill the enemies on the way since you need to have a clear path to Girtas. The enemies still give poor experience. The shackles/books are a good drop chance but given how many you need to use any of them for crafting it feels lack luster. Most will end up using the shackles to turn in for reputation (not worth IMO).
You have to clear the 4 death priests before you can hurt Girtas. These should have increased drop rate and quantity of fragments of soul stone as they're just damage sponges to make the encounter longer.
Girtas is extremely tanky and this encounter is definitely not balanced around being level 60. I wouldn't think most first character level 65s could do it (depending on class). I've run this on T3 multiple times and received 0 from him every time. Needs a higher experience reward for finishing as well as more drops besides a potential kaiser.