So I had purposed this idea before but I'm still sticking to my guns because I think it would be a fantastic idea so here is my JA idea for what should be next on the BLU...
"Distorted Beast"
recast every 5 minutes, duration 1-2 minutes
Description: Converts Physical Magic damge to Magical Damage
This would act as a MNK's formless strikes, but for our physical magic only, because lets face it, most BLU's are more properly geared for physical spells then they are magical, and in a pinch, this JA would be fantastic against NM's for dealing damage with out feeding massive TP to the mob. While also dealing magical damage. If you even wanted to, you could give physical spells a type of elemental alliance under this spell, or just make it simple magical damage. If you were searching for elemental alliance, you would simply look at what skill chains these spells can open, and give them that element, yet this part could be more complicated, so I would say stick to the idea of making it just magical damage not of a elemental alliance.