Sorry to continue the unrelated topic, but I had to say this kind of set up sounds cool. Never done all Axiom myself -yet. Maybe the Alias, if powered down, could substitute the Envy in some level...for those flat to fade shots? I dunno.
A word of advice regarding the Defy: it may start of somewhat identical to N Photon at similar weight, but some seasoning definitely makes it turn a lot more. If my experience w/ 168g 1616 stamp Defy is of any indication of the "norm", I wouldn't trust the Defy in a head wind. I was caught by surprise when the seasoned Defy turned and burned in a decent head wind, while my 168g P Photon just cruised straight and still faded a little in the end.
A heavy Proton might hold its stability better according to its description but I guess this WD40-plastic isn't an option for you Snap-it If I was to try this kind of set up, I would use only fresh max weight Defys of step down to Wrath which still works fine with the Crave (then again, the N plastic on Wraths was like reaaaaally soft).
Of course, just my 2 cents
Why would you need to substitute the Alias for the Envy when the Envy is already Axiom?
I do often run an all Axiom bag with Envy/Proxy/Theory/Alias/Inspire/Crave/Defy I find myself using the Envy, Theory and Crave on the vast majority of my shots, but that bag covers just about every shot I can think of. If you really need OS, you could add a Fireball.