Since the BLU body piece gives +15 Blue Magic skill (which, for all intents and purposes, blows +5 Magic Acc out of the water), I'd probably even say RDM/BLM > BLU/WHM/SMN on the Manteel.
I assume no BLU mains were in on the lot order discussion
That's why I keep mentioning suggestions - not because I'm just trying to be a dissenter, haha. Haste is nice, but Magic Acc on body is crap for BLU considering AF. If it weren't for nukes, the same could probably be said for RDM on that piece too, but with /DRK and /BLM I suppose we could make use of the Dark skill too.
In the majority of cases, I'd say Accuracy > Haste > Magic Acc for BLU, at least until more end game BLU gear and merits come out. Magic Acc uses are limited to a handful of endgame fights (and then, usually only if it's safe to AoE). Sticking Frightful Roar or Enervation, and unresisted Mind Blasts or Heat Breaths are the only things that come to mind. The Nashira Turban is pretty nice for BLU given the spell interruption and +5 M. Acc on a slot that otherwise sucks for magic-based spells (AF isn't bad but..Turban significantly better). Other than that Nashira kind of "meh" for BLU, especially compared to Homam.
Really, when all is said and done, this all might not matter because it will probably be a long while before we get a BLU main who'd declare Nashira as their lotting rather than Homam - possibly not until BLU AF2 and AF1+1 come out, which will probably fubar everything anyways.