Just sharing some opinion about all that "GEO is a better buff job than COR!" floating around recently. Pure support wise, while GEO buff/debuffs are potent than COR buff, and being a more versatile mage job overall, having limited buff slot is still one major weakness. On the other hand, COR is better as a job to do multiple buffs for different pt/jobs, in fact it's a better job than BRD on this aspect as well, thanks to 8+ min roll duration.
For example, most Incursion pt tend to put Crowd control jobs like RDM or BLM on different pt from DD pt, and they tend to ask for macc buffs to land stuff on higher ilv. On COR I can just do macc roll on 2nd pt, and switch back to DD pt for double DD rolls. In fact I can still do mage rolls for mages in the DD pt. On GEO you'd have to sacrifice a buff slot for macc/meva-.
With PR job points category COR buff can stay longer than 8 min, just switch to 2nd pt before NM, macc roll can stay pretty much the entire duration of the fight without the need to reroll.
