Apple has never offered I/O customization such as you're asking for, and there's no workstation I've seen that's offering 32GB of ECC RAM in a sub-$3k price, unless they're using small DIMMs across 12 RAM slots or something (HP sells the "default" 840 with 8 x 1 GB sticks, for instance.)
This sort of list of demands is essentially "I want more for less."
Reread my post. I never set a price. Also, until this year, Apple never offered customized wristwatches, so a higher-level BTO scheme for a new Mac Pro is not far fetched if a company is truly forward thinking and is not just Greenwashing to seem cool and environmentally benevolent. Professionals should know and understand that choice is a good thing when it comes to component specifications. Know your ROI.
Here's an example showing that custom builds are indeed possible when the grunt-of-task is more important than thinness or bling. Imagine being able to run OSX on something here: http://www.boxxtech.com/products/workstations