Our oringal group was as follows:

PLD, PLD, BLM, SMN, BRD, BRD, WHM, SCH

Now days we have the right geared alts to try our different tactics and get things done quicker:

T1: PLD, PLD, BLM, SMN, BRD, BRD, WHM, SCH
T2: WAR, DRG, DRG, BRD, BRD, BRD, WHM, SCH or same as above when we're not doing the enrage tactic.
T3: People usually switch into Spiritbonding gear here, so as long as we have a tank and a healer, we're not too bothered.
T4: PLD, WAR, BLM, SMN, BRD, BRD, WHM, SCH

That's our Free Company though, we have about 8-14 people that switch in and out from time to time, depending on who is online. The party composition doesn't change much however.