I'm not following the logic here. When one company owns more of the market, they have less competition. In this case, SPG has effectively been eliminated so that's less incentive for Marriott to decrease prices. I think there's virtually no chance there will be any kind of brand or category decrease.

As for my opinion, they will likely stay the same, with a few adjustments where a hotel was over or under priced. Then you'll see the normal annual changes, which tend to be mostly increases (at least for the properties I seem to care about ).