Ok. This may be way off the mark. Admitidly I've not read every word of every post. I would square up your ends with some of the golds/tans with half hexies or whatever shape that would be. Or just chop of your points - your choice, obviously. I would then (if you have enough) do a thin border of the blue sky/cloud fabric. I think your quilt is fabulous but tends to be a bit dark so I would want to brighten it a bit. After the thin blue 'stop' border, I would go with the tans/golds that you have for an additional border.
I think a thin border of the blue would highlight that fabric in the quilt and make it 'pop' a bit more. And the tans/golds would brighten the whole quilt. If you did a 1" blue inner border and then a 3" outer border it would not increase the overall size that much since that does not seem to be your goal. But you could easily increase those sizes if you have enough of those fabrics to get to whatever size you want. Perhaps a nice sofa throw if too large for a wall hanging?? I don't have nearly that much wall space in my house, lol!
Good luck. You've done an amazing job so far!