For me, I bought the following:
All ranks
Stat reset (because I screwed up, and went all VIT instead)
Chocobo Full Barding
The hubergeron (chest piece)
The ul'dah hoplon
The ul'dah winglet (because I think the scimitars look rediculous, but also for the increased accuracy)

I'm still using the winglet and hoplon at 50 because I haven't found a suitable replacement, and have yet to get the GC level 50 weapon due to be being story blocked.
I haven't really done a lot of seal grinding, so that is just from me picking up a fate here and there while questing.

Hope that helps.