The "KMS and Gallium crap" IS the open-source implementation of what the FGLRX and nVidia blob do internally.
At the moment when AMD put the effort into the Open Source drivers, there was NO open-source infrastructure that did what needed to be done. And their binary blob could not be open-sourced for a variety of reasons.
The nVidia and ATi binary drivers consist of millions of lines of code which was made by a team of dozens of full-time programmers over more than 10 years. You are expecting three or four guys to replicate that work in a year.
You are not being realistic.