Ah-ha. Same issue -- different terms. Would put stress on the large pieces unless there is some quilting there to subdivide the 5x7" house. I've seen quilts with that amount of total trapunto (just with skinnier pieces). Even adding an full extra layer of wool or poly batting won't change the weight much. It's the amount of microfill stitching that typically impacts the weight the most.
Doing the trees would be cute. You could create channels on either side of the trees to do your microstippling & it would really bring out the heart shape.
