I think it's pretty heavy on brickcount
Well, as compared to what? Like I said, it's the ratio that matters
For this style of cubescaping, you can assume 257 bricks used per square 64x plate (16 x 16 rows of 4x cubes, 1 zone brick). You get detail to a resolution of 4x cubes, which is pretty detailed. For traditional, "supported", cubescaping, to achieve the same 4x cube resolution you need more than that number, so that none of the bricks are floating
I mentioned the brickcount to detail ratio specifically, sure you could make terrain that uses less bricks but it would look worse.