You have four with 'inside' flowers. Try using those to mark the corners. If you hate the one with the large square, consider appliqueing a flower similar to the others, into its middle. Then use it in the center of the layout. Then work the others around, with the heart block in the center top as suggested. Separate the like blocks, such as the pointed ones.
Truthfully, all the blocks are beautiful and once you put the sashing on, I don't think you will have any problem with the layout. It will all go together and will be lovely.