I would think it would be much easier and simpler to just implement buffs in a Bardish style, similar to the way I had it setup in the second build from the link in my sig.

FNC/MKT
Fog- Increases Evasion and Magic Evasion of party members in range.
Incantation- Increases Healing, Magic Attack, and Enfeebling potency of party members in range.
Bewilder- Decreases Enmity generated of party members in range.

RDM
Temper- Increases the attack of party members within range.

Different buffs, different niche to fill, and lets RDM get back to doin damage like BRD's can.