Id say start with Marrowgar, LDW, Gunship, Rotface. They are the easist in my expierence. After that Dreamwalker and Blood Queen is not to bad and if you have good DPS Fester and Saurfang would be good next steps. Princes was annoying and took some learning but once learened goes pretty well, just have to plan ahead were people will be standing and where they will be moving to.
Putricide and Sind were the hardest for my group and we have yet to attempt LK HM.
1 Tank 2 Healers
3 Healers (The enrage is easy its just a metter of survival and watching threat)
1 DPS 9 AFK
2 Healers (the extra DPS helps reduce how many marks you get and thus ends up preventing more incoming damage then a third healer would be healing anyways.)
2 Healers (3 if you have the DPS to spare)
2 Healers (Did 3 when learning the fight but only really need 2.
Addon Author: What's Next? - AllPlates - Sudoku - Death Clock - Super Loot