Well, if its a letter to Santa post then...

For DRG:
- Immunity proc to almost any damage during Jump animation (or proc a buff that lasts 1 or 2 seconds)
- A way to reset all Jump skills' CDs
- An impaling skill that will throw the enemy away and damages them more the closer they were and the further they flew!!

For NIN:
- An actual lag-proof Mudra System
- That Assassinate can be used from further away from the target (or at a larger remaining HP %)
- A shorter CD for Shukuchi T_T

For MNK:
- A toggle skill that cancels MP/TP recovery which will make skills draw MP instead of TP (and cost double amounts), but that while during such effects GL will have a double bonus!
- Kamehameha, Henki-dama, Hadou ken, etc etc :v