I think there is something to be said for Scheme as an intro language. Knowing the "full stack" of computation doesn't need to end at NAND gates, it could just as easily end at the lambda calculus. In fact, I personally would prefer it that way.
There's also a risk you'll set students back if it's not effective so there are definitely ethical concerns and it requires interrupting a professor's load for the quarter. That said, CS educators conduct research like this all the time and there's probably a lot of value in studying this kind of change.