I find the more I play with quilting designs, the more they look like my quilt designs but without the applique and quilting.
The same type of designs appeal with or without additional colour.
I am designing quilting block by block, like I do the pieced and applique quilt top, and modifying the design by adding and taking away lines of quilting.
The biggest difference is that changes within the block design can translate an elaborate filler design into a stand alone motif … though that is really not that much different to what I do with a pieced or applique block, sometimes by modifying the block design … sometimes by just modifying the contrast.
Working block by block makes designing a whole cloth quilt much less daunting!
It does mean that after just a few months of concentrating on quilting lines I have dozens of whole cloth designs … and it is getting more a more difficult to pick just one.
Then there is the problem of choosing the fabric, the colour as well as the feel of it, and the colour of the thread, and if it should be a strong contrast, or matching, or somewhere in between. Or perhaps more than one colour!
I have reached the conclusion, at this point, that a contrast like that above is my preference, and if some areas need additional background fill I would use a thread which would disappear on the background fabric.