Personally I've never dealt with a setup like that. It looks like a good starting point. I don't know if I'd machine down the divider just yet. There's got to be some research out there on it, I'm thinking it will give it some properties similar to that of a single plane manifold. And those runner openings are really close to each other. I'll do some homework on it.
Have you considered a completely fabricated intake and plenum at all?