Sorry, company came over whilst in the middle of this.
Try adding alternating points to the boundary- /\/\/\/\ sort of thing, like a paper cutout
EDIT: rofl oops, I thought you did the matte on the updated pic, but I mistread
A scalloped edge eh? I'll give it a go.
I think it's the green around the edges that makes it seem strange to me. Maybe if it was just the black outline?
That is what it looked like originally. The green outline is a suggested experiment.
or perhaps a darker green?
I'll put up a prototype of that too.
EDIT: Added a darker edge. I feel the matte doesn't seem to add anything to the design. Perhaps with the zig zag design. Working on that.