i think it is a pretty cool expansion.
i think the trials are potentially tuned towards a particular style a bit too much. I would think a non-time equipped knight would have a hard time tanking a lot of the progression stuff. some groups try to use 2 clerics on a defensive warrior to kill progression bosses. i am not going on direct experience with all of them, just kind of stuff i've heard.
part of the problem is just inherent to EQ and that is the biggest flaw with the game really, but i think some of the encounters could have been done with a bit more creativity that didnt favor massive healing on a defensive warrior.
i do like the fact that it is challenging to get places, we have all been lulled into laziness with how gimped down the game got with PoP (graveyards, free travel everywhere). i was on a CR last night and forgot to reinvis after hailing the magus to get to Natimbi. so my laziness got me smoked
granted i am not really missing the days of going to neriak for your large coffin run to recover from a wipe in Disco or whatever

but you know the zones are small, and its fast to get back, so it's all good =)