The only problem I can potential see with this proposal is that the courts might view it as a violation of separation of church and state, on account of specifically setting aside days for rest based upon one particular religion. Now that's not to say I oppose this bill (I don't) but I would recommend perhaps something more along these lines, in order to help you guys avoid potential legal wrangling:
I think this works better because it doesn't single out Sundays and thus, single out Christianity as the only religion that would benefit from such a move. It also guarantees at least one day off of work, which will probably in some fashion create jobs in companies which have relied heavily on forcing a few workers to work overtime on a regular basis.
