I like the idea of PoP zones being distributed far and wide, although I know very little of PoP, having done 3-4 pickup raids there and that's about it. I loved the Plane of Tranquility theme though and have it on my Ipod
[You must be logged in to view images. Log in or Register.]
Anyway, getting to my point, I would avoid having access at the bottom of dungeons due to the fact that the uber-raiders running in and out are going to disrupt anyone actually playing in the zone. They would either kill all the mobs they aggro or train everything from zone in to zone out because they are in too much of a rush to get to their destination. Either way disrupting the lower level groups. Bearing in mind especially that a 64 man raid will be coming and going in their 2s and 3s over the course of half an hour or more. That's a lot of disruption.
I experienced this kind of behaviour whilst hunting in The Grey. Players would sprint to the temple and back out again to Mons Letalis (iirc) with a train of every worm or golem or whatever they could find on the way. It never inconvenienced me, being outdoors, but imagine that happening whilst you are camping in Sebilis or Lower Guk? (Or Kedge/Hate which are actually suggested in the first post).