So, I've spent a couple weeks doing a lot of data gathering, math and programming/scripting to come up with some sort of proof as to what gear set(s) are BiS for SMN and why.
This thread on the SE forums shows some work done modeling the damage formula around numerous sets of in-game data. (not parses)
From there, I did some work to verify the formula (I did, about 30 times over with varying skills and gearsets at level 50), and documented my findings in
this thread, also on the SE forums.
In the process of this validating of the math, it became quickly evident that the actual stat priority was: WD > INT > DTR > CRT > SS