If one goes to max perfection then drops back and casts, does the damage bonus and luck bonus still apply?
When you say drop back, are you saying you reach "Achieve perfection" and step back and use spells, or you loose perfection?
Either way, the perfection damage bonus is melee only. If you loose perfection then you loose percentage. As far as the luck bonus, not sure and don't think there is anyway for a player to determine as the luck bonus doesn't show on the status bar anywhere. Some say it scales with perfection, but the description says it only applies if you have achieved perfection when the kill stroke is landed.