1. Plenilune Embrace+magic fruit+winds of promy? Some +MND stat spells are good although it's not really needed IMO, would rather set usual DD/stun/sleep spells to keep some form of versatility when situation changes.
2.Sub-zero smash(para)/Filamented hold(slow)/Actinic Burst(flash)/headbutt(stun)/dream flower or sheep song(sleep)/blank gaze or geist wall(dispel)/Disseverment(Poison)/Aureral drape(blind and silence)/benthnc typhoon(def/mdef down)/Magnetite Cloud(gravity)/Regurgitation(bind)/Demoralizing Roar(attack down)/Infrasonics(eva down)
Depending on the mob may remove some if it doesn't land or not needed on the target.
3. I don't consider BLU to be enhancing job at all with long recast time of Diffusion. I guess AoE refresh in Salvage if healer is a WHM? Or AoE attack buff before zerg? Or diamondhide which isn't that effective and would rather accession SS......
4. Would probably keep magic fruit/P.embrace/winds of promy/Sub-zero smash/Filamented hold/Actinic Burst/benthnc typhoon/disseverment at least, other debuff depends on what benefits the situation the most I guess.
5. That I'm totally not sure, I haven't play BLU to deal ranged dmg only for very long time since I have an empy COR if I need ranged dmg, and most of the time ranged dmg are not really really needed nowadays(even in VWNM I just run in and efflux QC and run away)