Your blocks are beautiful. We are our own worst critic when it comes to piecing and quilting. But, for the inner circles, this is the method I would use. NOTE: I would test this first on other fabric first, just in case you hate it.
https://www.youtube.com/watch?v=oK4Wv1l61J0
Edited to add:
The beauty of this method is that your pieced part will be up to you so you should be able to tell that you are not cutting off any points.
One thing he did that I would not do is to iron the seam open. I would iron it to the inside of the circle so that your pieced outer edge can lay flat. Your outer circle already has enough seams and you don't really want to have to notch into it to get the outer part to lay flat by cutting into your seam allowance.