Yeah figuring out a good eliptical for that transition is golden. Though I've noticed after hopping on a sleepy stevens mid season that having those diagonal carbon load bars bring a ton of perks.
If I could design a deck though, it would be flat slightly past the inserts with a lesser angular reverse camber that becomes flat as well, while the elliptical for that flat-flat transition be weighted more in slope towards the reverse. All while having diagonal pop rods in conjunction with a base pattern conentrating on strength and responsiveness on the edges of the eliptical for the flat(base) half of the elipical.
You guys have a dream job, getting to play around with this stuff.