I wonder then, do any flash upgrades improve data for the 07s? I have a flash for the SC that is installed.
Don't think so.
There are 3 distinct base firmwares for the Elise/Exige ECU (and revisions in between, of course): '05 (original DBC ECU), '06-'07 (DBW ECU), '08+ (different CANbus data rate and info for new dashboard, other logic changes).
An '08+ firmware can run on an '06+ ECU and vice versa.
As far as I know all of the different factory and aftermarket tunes alter only data and conditionals in the tune, but don't graft sections of code or entire features from tune to tune. For example, I don't know of any tunes that add additional data in on their own - just tunes that are based off of the "black dash" firmware and thus get the '08+ CAN feed (but require a black dashboard for now).
It was my understanding that a few tuners have worked to graft "black dashboard" CAN support into the '06-'07 firmware and vice versa ("white dashboard" support into the '08+ firmware) but I don't think anyone has been successful in doing so. All of the "dashboard change" flashes I'm aware of simply give you the base flash from the year your dashboard belongs to.