Learn as you go

I am still trying to figure out how to make a proper set of coasters. They should be a quick project for me, but I keep stumbling on the finished edge. Binding such a small object has proven to be much more frustrating than it is worth, with the binding taking me longer then all the rest of the project. On my last set that I made, I attemped something a little different. Let me show you from the beginning:

I reached deep into my scrap bin and pulled out some coordinating scraps. I put them together with as little rhyme or reason as possible. I was trying my hand at improv piecing.....

After the scraps were together, I made the quilt sandwich and traced some appropriate sized circles for the finished size of the coasters.

I quilted in those circles, then cut them out. See? Almost done.....

Then a tightly zigzagged the edges to finish them. I could have done it even tighter. If you have a serger and know how to use it, it would be very handy in this last step (I have a serger, but the tension never seems to be right; it intimidates me). Et voila, a set of mug rugs.

I would love to have a beautifully binded edge... but am thinking that may be beyond my realm, and I hope this could be good enough. Thoughts?