I could definitely see them getting rid of the 13" MBP, but it has been positioned as the model you're pushed to via anchoring, as it seems like a deal (if that makes any sense). It does seem like the MBAs are filling in this role, but I don't really see how turning every model into a variant of the MBA would match up with Apple's standard product strategy.

Agree that there likely will be some changes to the larger models along the lines you're proposing, but I think they will still be somewhat distinct from the Air.