instead of this stupid argument why not just add in incendiary arrows for firestorm, use kindle or read the wind when it runs out. Then you can just sub whirling defense for penetrating or conjure or whatever... of course then its a completely different build and not at all what the op was using or talking about.
I think its a cool build, but yes its got some points of contention. If you posted it, you implicitly asked for a critique (you knew this right?). Unless this is part of a team arenes/HA build, there's good reason to include a defense and perhaps a self heal. That reason is 'it's yo butt, cover it'.
Conjure flame: at level 10 its +11 fire damage for a 10 energy (non-expertise mitigated) enchantment (which can be shattered, but possibly lasts 60 secs)
Incendiary arrows @ level 12 (where I'd put it) 5 energy (3 with even 8 expertise) gives you 8 secs with every arrow interrupts/burning for 3 secs (a LOT more damage)
kindle arrows (again with an assumed WS of 12) 5 energy (again 3 with mitigation), +20 fire damage
In conclusion, my thesis is that WS offers a *ranger* FAR more fire damage, with far less energy cost than any fire ele spell can dream of
