Saw a segment on one of the quilt shows on PBS where folks send in quilts that they're unhappy with and two experts give suggestions on what can be done with it. I was impressed with the ideas, such as:
-Putting borders around the squares or sets of squares
-Changing the border (add, remove, change sizes, use more than one to pull the focal color out)
-Adding applique over the top to pull out the focal fabric
-Covering an applique that was in the center of a quilt that detracted from the diagonal design flow (art quilt)
It surprised me what a difference these ideas made. You might consider posting a picture and see what ideas the board members can give you.