OK, I have looked over a fair bit of info (including the suggested links), and have thoughts/comments/responses.
I should have clarified that my "base malt" mix is in part driven by what I have on-hand -- I didn't have *quite* enough 2-row, hence the extra Maris Otter. In past recipes with similar flavor goals, I've found a measure of Munich malt in my WCIPAs also adds something I like. I've ditched the crystal 60 initially indicated (don't remember why I put that in there, anyhow), and just used crystal 40, as well as throwing in some biscuit malt. Past recipes of 2 row+Munich+crystal 40+biscuit have worked really well for me, so I'm going to stick with that general malt combo.
I did get a chance to read through the hop survivables pamphlet from YCH, and found it somewhat useful, but not entirely what I need in my case. The blending principles seem defensible, but the limited coverage limits its use for my current hop stash. Additionally, without individual lot/year analyses of my particular hops in-hand, I'm in educated guess territory at best for the hops that *do* overlap with my recent acquisitions. I've dug a bit into the available data for the hops not in the YCH literature, and have something to go on now, at least. So...it at least gave me food for thought, and did help clarify my hopping strategy!
In any case, as I read more about the various hops, I'm going to revise my initial thoughts, and save Strata for another brew. At the moment, I'm leaning towards Waimea+Wai-iti+Cashmere as whirlpool/dry-hop...but I gotta decide quick, because I'm just heating up for the boil! If I were really worried about "classic" WCIPA, I'd probably swap Cashmere for Cascade, but I do so much with Cascade already that I'm going to reserve that for yet another batch of truly classic IPA. I'm maintaining Bravo as the bittering hop.
As a creature of habit, getting the HOPBOX has been a pretty good way to break me out of the usual mold. I plan to write up a review for my blog before too long...
Thank you, everyone, for your thoughts and pointers to resources -- I truly appreciate it.