Just a couple of friendly words of advice.
I would suggest you have at least one memeber with WHM leveled as the can be very useful on bosses as a single RDM isn't going to be able to solo heal the MNKs.
BRD > COR (no offence to CORs) but if you can only have 1 buffer, take a BRD. Double march is a massive plus for normal mobs. March/Min for bosses is normally best (more damager per TP feed), or double minuet for MNKs who are 2hring.
Make sure your THF has TH4, the drop rates are bad enough with it, but it is slightly more barable.
We have a few people with BLM leveled, and we did trial them coming as BLM for stun on the bosses, but tbh they weren't very useful, they were normally coming as something else. But that was a subjective decision made by our group.
And the last peice of advice I can give is, do your research. Not just the leader, but the whole group need to know each zone in order to effective.
I know this was unprompted, but just thought I would share my experience of salvage.