I would certainly decline housekeeping for 1000 MR points, I dont generally bother with it anyway, other than on longer stays.
Sounds like a good idea to me.
The 500 SPG points seem on the face of it insanely valuable bearing in mind SPG awards 2/3 points per $, as opposed to 10/15 at Marriott. That might suggest Marriott would need to offer about 2500 points each time but SPG redemption rates are not that much less than Marriott. The SPG top redemption rate is 30,000 per night as opposed to Marriotts 40,000, despite the fact that SPG's earn rate is 1/5. I must admit on an earn/burn ratio I've never seen that much point to SPG, although I admit the scheme is very highly rated in these parts.
Overall I think the 1000 MR points is very fair...