As tonight is night #161 in FS Marriott's this year, here's my thoughts:
-Your observations are more or less equal to mine. More and more it seems to be just whatever room they have available, and 4-5 times this year I've been given rooms with double beds, even when booking king.
-There have been times that I have been given great rooms, presidential suites twice, and just better than standard rooms another 4-5 times.
-Claimed the $100 elite gift guarantee once, and only after being eligible to claim it 3-4 times at the same property, after a really poor check in experience.
-Hotels do seem to be more attuned to customers this year than last.