My exact first thought was a house, but then I saw the houses on the four sides ... then, I thought waving flag and noticed the flags in each of the corners.
Then, I thought: Eagle - - and kept reading and noted that you didn't like the eagles that were available to you.
And, I read the post about the flowers looking like fireworks, and that was a dandy interpretation, but .... hmmmm...
noted the posting about the liberty bell or the tree ... and thought: Tree of life! It is an old pattern, and usually seen on point, but you could set it straight up and down - - it is your quilt <g> you can do whatever you want to do!
The Baltimore album-type wreath is a viable competitor for the center of your quilt, but ...
Bottom line? If I were to see the quilt you put on the design board and told me that this is the way it was going to be, I would say: okay! Lots of work and a nice bunch of pieceing and applique.
You have good instincts ... and, what you have put there
HEY! How about SUn bonnet sue and overall bill or Sam/whichever he may be ...
I like all of the suggestions better than the bear, but I liked the bear because he was dressed up patriotically .... you could even have sue and/or Sam/Bill doing something like looking up at the fireworks or saluting the flag ... or ringing the liberty bell ....
I am done thinking now ... <g> I can hardly wait to see what you are going to do.