PS3 cannot handle FFXIV full 1080p+ graphics, hence the reason it is set to 720p 30fps.

the only things you can do to combat fate lag is by
- turning off all effects for You, Your Party, and Everyone Else.
- removing the display of Names, HP bars, and flying txt
- turn off display of headgear and sheathed weapons
- and by playing in non crowded fates

if you have the money
- install a SSD into the PS3 to help loading times

That all you can pretty much do. with these settings you are basically removing the amount of stuff the ps3 has to load. I believe character models get first priority, so don't be surprised if you don't see any of the enemies/boss of the fate till they are dead.

I play on PS3 and PC... I prefer to game on my console, so I sacrifice the graphics and few bonuses the PC version gets for my preferences.