I brought this up in another thread actually.
If you're leveling GLD, you're almost definitely going to be going PLD. As a Job, you have access to 5 cross-class abilities. That may sound limited, but seeing as PLD only has access to 6 in total, it really isn't.
Currently PLD has access to: Cure, Protect, Stoneskin, Raise, Mercy Stroke, and Foresight.
All of those have at least limited use, except for Stoneskin. Being a 3 second cast, you'll never get to use it properly on a PLD tank. You'd almost definitely get interrupted before you got the cast off. You could cast it pre-pull, but I still don't really see the point as it only absorbs 10% of your health in damage. That'd be gone after taking only a couple hits.
I'll be running with Cure, Protect, Raise, Mercy Stroke, and Foresight on my PLD for sure.
Edited, Aug 20th 2013 6:08am by Teracide
FFXIV: Raxion Gunsoul - Brynhildr - 50PLD 50SMN 50SCH 50DRG
WoW: Raxion - Greymane- 90 Druid
FFXI: Nion - Asura - 99 BLU, PUP, SMN, DRG, PLD 50+ DNC, NIN, MNK, THF, WHM, SAM, WAR