Another way to utilize that panel for a quick quilt!
Still needing that quick quilt and found just the right panel? But you say it's a little "unsquare"? Don't despair--you can still use it. First, square it up as much as possible so that the individual "blocks" printed on the panel are as square as can be. Your next step is to cut those printed blocks apart. I know, there is that point when you say "but they still aren't totally straight!" how do I figure this out???
When faced with that challenge, my goal is to cut so that the block gets as square as possible. This means sometimes trimming just a bit off the fake sashings between the "blocks". Even though it will result in those fake sashings being just a bit wonky, I'll put wide enough real sashings (and probably use something either the same color or close color relative) to seperate the "blocks" and keep the eye from focusing on the wonkiness. My quilting will also be designed to make the block, not the sashing, where the eye wants to focus.
Now, let's talk about the actual block from the panel and how to quilt it. If it's printed so that it appears to be individual blocks, each centered on a plain background like it was appliqued, then I treat it like applique. That means doing as little actual quilting on the printed picture as possible, just like I would with someone's wonderful applique. Sometimes a little quilting is needed to secure the bat to the "applique" and backing--in that situation, I'll use a thread the same color of the applique and do just enough quilting to keep it secure and quilt only where it makes sense in the applique, like along the edge of an object in the applique picture. I would not do this if the piecer has used a decorate stitch to secure a real applique or without their permission! Then in the background of the picture, I'd use close stitching of some type--narrow lines, tighter swirls, McTavishing, etc. This needs to be done in the same color of thread as the background so that the applique is the focus and the more dense quilting enhances the applique and does not compete with it.
Next, I would be sure to quilt other areas of the quilt with some degree of quilting density so that the quilt stays flat--otherwise the dense quilting around the "applique blocks" will pull the quilt out of square. Now back to those sashings around my not quite square blocks--I don't want to draw lots of attention to the sashings--especially if like the quilt below the sashings are of different widths. So I'm going to use a quilting design that is not very dense, yet holds those sashings securely. The design also needs to NOT edge right next to the "not square" blocks--I want the viewer eye to see it as square. And since the sashings are different widths, I don't want a design that doesn't work with various widths. Look at the quilt below, done as a sample quilt for the Lil' Red Hen Quilt Shop in Paola, KS. Check out the quilted "blocks" and also sashings. Notice that only when you are looking for the wonky fake sashing and see it up close can you actually see it.
What you may not be able to see is the FMQ spider webs in the borders that are dense enough to counter that dense quilting in the blocks, that and the line of pumpkins in the long strips of blank fabric. Don't be afraid to use panels!