She could go an entirely different direction with this pattern by setting the blocks on point and "floating" them with a coordinating or contrasting fabric. I have just started working with a mixed collection of almost-the-same-size blocks. By setting them like this, I can adjust the size of the outer triangles to come up with a consistent size, in this case 18", and I'm hoping nobody will be likely to notice that the original blocks are not precisely the same.