What really needs to happen with T2A is that its original purpose is finally lived up to. The whole reason that there are empty spaces within that area AND a lack of wander healers is because, as Designer Dragon put it, it was specifically designed as a frontier experience where players would have to join together and heal each other and be there for each other, and it would be largely without the support of guards or healers.
Unfortunately, soon after the release of T2A, Designer Dragon left for SWG, and the following design team either couldn't make it work or just simply chose not to. But it was originally designed to be exactly that.
Of course, Fel would be a different story, but in Trammel, it could still be used as intended. The only thing the DevTeam would have to do is make a slight adjustment to how housing bases work in that the house plot would have to ensure its base was above the highest curve in the ground, and then the front stairs would have to extend in a manner that allowed entrance to the house. Not really a huge deal (I mean, SWG even placed awesomely into a very hilly environment, so possible... just needs programming), but would require some update to the housing system.
In the end, it would be an interesting part of an overall revamp of T2A which, to me, could also herald an escalation of the Terathan/Ophidian war and perhaps introduce the Solen faction into it. There's so much untapped potential story-telling and history in this area (not to mention an implied tunnel between the Ophids and the Terathan Keep that is useless to us humanoids) that it would be nice to see it the subject of an update.
Just my thoughts, but I'd prefer them than to ever see cross-shard anything. Hell, I don't even like battlegroups in Warcraft.