Yep, it was total waste of time for me most of the time lol. You're put in a room full of OP mobs, then you have to kill either of the two architects, and open the doors... in 10 seconds. Yeah, tricky indeed.
But now since I have a dash ability (Whirling Blade) I'm having an easier time killing the architect. But still difficult to quickly find the Stone of Passage and unlock one of the doors. And I've never got a unique drop, eventhough I managed to kill the architect three(?) times.
I can't wait to be an assassin with the ascendancy class! It sounds amazing. And don't worry about the difficulty, I like it this way. And I hope it will still be difficult even when my character is in high level, otherwise it might get boring once I'm there.
After a while you learn to kill mobs to gain more time back on the clock and how to go about that in trying to manage the timer. Than you can work on taking down the Architect in chunks of need be. I've had times where there was over 20 sec remaining on the timer after it was all cleared so I just used a poral to leave instead of waiting around.
Some times I'll clear a little bit of one way towards the one I don't want kill then I'll move and clear out going to the one I want. Depends a lot on the loadout of the room you are in as well. Some times its just bad and you are not going get anything done.