Unique Ways RDM can utilize it's Manameter

[PatronasCharm]

Yeah, RDM can Raise / Cure... but what-if:

-Certain Spells only were accessible via White or Black Meter Gauge, but also cost MP.

Here's my thought:

Haste: Party Wide 10% Increase to Auto Attack / Ability Recast / Spell Speed. Uses 1500 MP / 40 White Mana
-
Temper: Party Wide 10% Increase to Direct Hit Rate. Uses 1500 MP / 40 Black Meter
-
Regain: Party Wide HP / MP / TP Regeneration. 3500 MP /50/50 White + Black
-
Would this be TOO much Utility? Or could this even work in FFXIV's perception of the RDM?