I think Xtabi now has one cliffside cottage with AC. Might be worth looking into.

Most boardies probably feel that Rockhouse is a little expensive for what you get. The gardenside rooms are relatively affordable, but the cliffside rooms/cottages can be pricey. Also, the restaurant has gotten lackluster reviews, as of late. I know I wasn't impressed.

Personally, I think that Catcha or Tensing Pen have a much better vibe than Rockhouse.

Seems like you are booking on pretty short notice, so a lot of popular places are probably booked. Somebody mentioned Home Sweet Home, and I would be remiss if I didn't recommend them, as well. We have stayed there twice, and will be staying there again very soon. It's a great mid-range resort that has all of the amenities you need.