its so great that you picked up that thread - we have the same tastes and ideas.
i like the look of stitches 23, 26, and 28.
you should make some samples - take some scrap fabric and some thread thats the same weight you'll be using but you don't mind wasting on samples.
play with the stitch length and width you should mark a couple straight lines down the scrap fabric and keep the straight line down the center of the of the foot.
you want to look at how far the stitches swing from the center line - this way you'll know how to lay them down on the quilt when the time is ready.
mark each test run with the stitch number, length, and width that way a few days from now you'll be able to refer back to the exact data that looks best.
of course add whatever other stitches you like the look of to the sample runs - you'd be surprised i've done this and the stitches i like best on my machine were all stitches i thought i wouldn't like.
the next thing we need to discuss is what did you do to applique the boots? is it fusible web and if so what brand.
some fusible web just doesn't look good quilted - you end up with a lot of needle holes that don't close up.
you can make a sample and test it out to see if your fusible web will close up after the needle penetrates it.
also can you do an echo stitch? i'm thinking you might be able to do some echo stitching around the boot. you can still leave the feed dogs up and just do a bunch of pivot around of the quilt.
ok - so thats your homework for the weekend. when is the due date for show submission - if your not sure double check some places want this stuff in way ahead of time.
its a shame you don't live near by cause we could all come over and help you out.