I didn't read all the replies so this may have been said, are you using an applique foot? it has a tunnel to allow for the built up stitches to have room underneath.
also I love your fabrics and dresden plate is one of my favorite quilt patterns

Lots of good answers, but I just want to say how much I LOVE your fabric choices. I think you should make the quilt. It's fabulous!

Mamadorian Do you have an embroidery machine? I
do all the centers on my machine use stickey back to hold in place no hooping they are perfect every time and take just a few minutes to run . If you dont have one perhaps
a friend would do them. Your Dresden plate is beautiful.

The stitches are not that close. I would go back over it again.

I don't use satin stitch on applique because of all the issues with trying to keep it even, bunching, etc. I use the blanket stitch or zig-zag. I think the result is better, and it's easier to go around smoothly when the stitches are not to tight.

I really like your dresden...it's lovely!!

Here's the center of my Dresden again and another circle I just did, after practicing and practicing. As much as you all have insisted 'practice makes you better', you're right. I think my newest circle looks a heck of a lot better than this first one. :)