Turned out very well! Hadn't heard of the reverse trapunto technique, but with the print you used, it probably would not have shown thru too well if you had done it the other way.
I was looking at Karen McTavish's book last week and she used COTTON LAWN for her top piece on some of her quilts. Thought "that is what the ladies on the board were talking about"! She did backing, batting, felt or whatever for the color, then used cotton lawn for the top. Guess it is thinner than regular cotton.