Yes, I only play alliance so an alternative would have to be found for Horde for Stockades.
I also agree that there are many drawbacks to Uldaman and Detention Block. Neither of them have any quick ways to return to the exit for the booster, for instance. The summoning stone for Uldaman is not only outside the cave but quite a distance away from the entrance to the cave, with a lot of mobs outside that could potentially kill an undergeared pair of RAF-characters.
Uldaman also has a lot of stunning mobs which is really annoying, since I usually drag a lot of mobs back to the entrance with me to kill them within range of my RAF team. This wouldn't matter if you have a friend doing the boosting of course, you can follow at a safe distance. However the amount of mobs and bonus bosses in Uldaman makes it worth it, I think.
After running Detention Block a couple of times I figured out quicker and quicker ways of navigating from boss to boss. A quick class with speed boosts, like a hunter or druid or rogue, possibly with booster rockets, could do Detention Block in less than 20 minutes, I think. The first clear of Detention Block gave both my RAF'ers over 250k XP so I decided to stay, rather than moving on to
Another plus is that Uldaman and Detention Block are pretty close to each other so it reduces a lot of travel time.
It just occured to me that the booster could run into Molten Core on the way back and then exit again, and would end up inside blackrock mountain, outside detention block instance.
I might try some different dungeons on a later session, will report back if I find something good.
For anyone else that wants to experiment, I suggest looking at Instances by level - WoWWiki - Your guide to the World of Warcraft to show the minimum lvl requirement (as well as locations).