BLM and SAM are nearly equal. Current difference at 75th is about 60dps, that's 1%.
Maybe physicals need balancing too, I just looked at balance between casters.

@Dualgunner
No SMN should not be caster only buff. As well as RDM should not be physical only buff. No other class has such limitations for their buffs. Just make that buffs independend from the dmg type to allow more raidcompositions to be effective.