My pally tank 3 mage druid healer team is coming along good. If you have room I would get at least 1 mage. Portals, food, & mage buffs are great. The pally tank is pretty nice. They are very good aoe tanks. I have not played a dk past 58 so I dont know about them. The druid healer is ok but I would think a priest would be the best healer.
You could do a pally, mage, shaman, priest + random dps class. With macros it shouldnt be hard to manage your dps with 1 button. The pally macro to tank is 1 button. I manually do avengers shield and anything else like hammer of justice ect.. Your healing setup will be the most trouble with macros.