I finally have some blocks to experiment with. I'm afraid my neutral sashing clashes with the bright setting triangles, and I'm not sure the alternate block is helping anything. Any and all comments would be appreciated!
The other option would be to just use a plain light colored sashing. I like the clarity that gives to the blocks. That's my objection to the coral sashing -- the block seems less distinct in the midst of all that coral. But as usually happens, the more I look at other options, the closer I get to embracing Bonnie's design.