Remember when it all gets quilted that the color of the thread used there can also help detract from the yellow.
A friend just finished a similar BOM project. She used a solid sorta marbled color for every other block, used one of the block colors [not yellow!] as sashing, and put the whole thing on pointe. It came out looking great. The every other blocks and sashing really toned down the yellow.
Then the quilting will also help.
ali