I've been tinkering with a similar deck recently (and yes, I have enough air nymphs to build it). Haven't settled on a final version yet, but have found that for the most part Aether mark, 6 phase shields, 3 quints and 2-3 immolation tends to work a little better (in my experience).
Reason being that only the first (and occasionally 2nd) actually end up being used to generate gas, and extra you draw can be used to fuel immolation when enough gas is on the field. Phase shields are more plentiful, and are reliable, since the AI will reliably target unstable gas with permanent control rather than your shields.
Unfortunately, reflective shields will shut down this deck and since you cannot pick a target for detonating gas, the standard trick of targeting yourself with your own shield up does not work.