Honestly, I'd start calling or emailing a couple of the names found here: http://www.framebuilderscollective.org/ and http://www.richardsachs.com/site/the-next-wave/

From my completely uneducated estimate, you do fall into that small percentage of folks who really do need "custom geometry" where a custom built frame is really the best option.

Kirk Frameworks (Dave Kirk)
Anderson Custom Bicycles (David Anderson)
Vendetta Cycles (Garrett Clark and Conor Buescher)

that's the top 3 that were on my list when I finally decided to order a custom rig. They all build in steel, but the links above will give you options in Ti and carbon as well.