I have tried warrior, healadin, sham, 2 firemage and it worked out pretty good. Since i only cleared the deadmines I don't have that much experience with that group but what I wanted was:

* Main tank to actually play on my main machine
* Range dps to avoid problems with positioning of chars
* as much Manareg as possible

The warrior is played by me, the healadin has a couple of hotkeys (one for each party member) and the dps is standing in the back and has their castsequences. I found out that it is much harder to play that group as opposed to playing my 2mage2lock1priest group because I have to dps, heal and tank as opposed to just heal and dps. But after getting used to it it worked out okay. The nice thing is that you have few mana breaks with palas blessing of wisdom and mana totem (which i didn't have at 22) up you can virtually chain pull the trash. I decided not to play that group anymore because the server i started on sucked and because I decided that I want my clothy group to get to 70 asap. When that is done I might find out that I do want to add a tank or something but I'll leave that for the future.
Whichever group setup you choose: Don't forget that having fun with it is the most important thing
Bunny