I would book the cheapest room. As a Gold VIP you have good chances to get upgraded to an execuyive room. Even if you don’t receive the upgrade you can buy lounge access at check in
Related: We booked a points stay some time ago for a couple of weeks from now. Prices were high. Now they have quite good cash rates (like EUR 120) for non-refundable bookings. This is a Twin and we have a King. As Diamond, I'm thinking a good bet to just book the cheaper Twin and count on an upgrade (Executive rooms are available).
Sound like a good plan?
Cheers.