WOW ... you did good ! Beautiful tops, the piecing in the 3rd is amazing
Muslin for backs and a solid or vintage fabric binding would be cool You only need a yard at most for binding
Be VERY careful washing them ... if they are hand pieced they are more likely to pull apart. DO NOT put them through a full cycle in your washer, you'll end up with a thready mess on the back. Soak in the tub and rinse well, wring out gently & wrap in a bath towel to absorb more water. You can dry in dryer just a few minutes, but if you can, its best to lay them out on a clean sheet outside to finish drying. :)