I actually really f**king love the idea of this.
Can make it a powerful Self Effect: I.E-
Regen Effect: +5 HP/tic
Refresh: +2MP/tic (1) - +4 MP/tic(2)
Spikes: Spikes Damage +25% - Spikes Effect Rate +10%
Enspell: Enspell Damage +25% - Enspell Accuracy +25%
And, RDM Empyrean +2 Set could grant these Buffs to others at a smaller rate, based on how many pieces... Like say... With Refresh.
2 Pieces - +1 MP/tic
3 Pieces - +2MP/tic
4/5 Pieces - +3MP/tic.
This way, Its a Pretty decent self buff, and RDM Empyrean augments it to be a pretty nice Party/Member helping buff too. Since RDM+2 already passes on some effect onto (73%~ Duration bonus?) onto others, It would be the same with this adjustment!
These are spitballed ideas, But i really like what you suggested. - All of my Likes.