I would outline all the different pieces - it's pretty by the way.
I also let the piece speak to me. I will say that sometimes if there are lots of circles/round pieces, I may use a stencil that has straight or angular lines and visa versa.
The narrow purple border, I might do X's in it - or I have a Bishop Fan w/ a rope border that would work perfectly for that - treating the outer 2 borders as one.
I am doing a Cars quilt for a little boy, so no curved lines in that stitching.