16K to Spend. Help me make the end all Upgrade.

I agree with Sbank.

There are many (but let's just say ten for argument's sake) companies that are at the top of the hill in speaker fabrication. You have already listened to a few and have found some don't suit your taste. How the heck are you going to design and build just one pair that you know the other companies haven't been able to build and reproduce music the way you want? Impossible.

Take the $16K and 'invest' it in Las Vegas. You'll have better luck and those odds suck.

Amen to Fredericks comment. How on earth can you get a pair of custom speakers made in that price range and not know EXACTLY how they will sound in your room. Crazy.
By the way, you really should have a listen to the Sonus faber GUARNERI MEMENTO's for a delicious and seductive intro into music making at it's finest. For your room they would fit like a glove and look absolutely stunning in the gloss graphite finish. Then get a REL Studio sub to finish it all off. Bigger is not always better. You should of course find a dealer that you can work with and set whatever you are getting up and helping to find an amplifier that works with whatever it is you are going to end with.

I have the Andra 2 with my Pass Labs X 350.5.
The Andra's have a dynamite piano black finish

I second the recommendation on the Rockport Mira - was one of the three best rooms I heard at THE show in LA when I was there. It looks like an unassuming speaker and doesn't draw attention to itself - quite tasteful looking. Sonically, it is so capable and balanced in every way. It would probably be my choice in a sub $20k speaker.

Because of your strange room shape/size, investing in a room equalizer like the Copland, Rives or Parc would probably be a good way to allocate your budget, rather than spend it all on speakers.