Obviously your project would end up smaller or would use more squares, but you can simply substitute them for any 2.5" designed project, like the recent Double Irish Chain sew-along here that is on the challenges page.
As I was going through my stash, I found a bundle of about 760 Y2K 2.5" squares and I looked around and realized that I could spend the rest of my quilting career doing nothing but projects based on 2.5" cuts. I chose a traditional "Flying Square" block.
With a 2" cut subunit, that would result in a 1.5" finished subunit. Your squares would end up at 7.5" whereas with a 2.5" cut it is a 10" block.
Here are some directions:
https://www.generations-quilt-patter...ilt-block.html
I didn't color my project at all like that, I used random scraps to make 9-patches + off-white tone on tone backgrounds.
Edit/PS: Once you decide on the pattern, I know I would be willing to help you with any math conversions you may need. But basically it is the desired finished size of the piece + .5" each direction for seam allowance -- except for triangles! But you can also make a bunch of HST (half square triangles) by sewing them down the middle, I'd just discard the extra trimmings as being too small for me to want to work with, but that's up to you! Plenty of traditional designs like Ocean Waves or baskets that could use those finished size 1.5" triangles.