I like that last one polar, there is a really nice feeling to that one.
The plain border seems to work very well, I think it looks better than the ones with the "glow".
I also second that Aesthetics should take as much time as he needs for this, there is no
rush, The final compilation will be all the better for it.
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I just had an idea...
If you are uncomfortable with such a clean edge perhaps you could somehow tie it in with a pentagon aperture type thing. Look at the bookeh in this photo for an idea. Just a thought, but it the clean edge really is nice as it is.
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