I see, it does make sense, thanks! I haven't used the Xilinx tools yet, but do work with the u-boot on many different boards, and got excited. Interesting to know how much more there is. Thanks a lot for the details!
If I understand it correctly, it's a bit like the device tree files in the kernel. The vendor might put out one, while the community might converge on another version for the same board (e.g. different devices enabled, different video settings, that sort of thing). Just these ps7_init files are much more sensitive to specifics, as you say.
In this case, wouldn't it make sense to generate a base or official Parallella version, something that's okay in general and have that in u-boot? (there had to be something already to be able to boot Parallella already, just move it into u-boot based on the gpl generated files). Besides that there could be (should be, hope there is) more community developed specialized files, just like for example you boosted yours? Then everyone who wants to build things from scratch just selects their choice of the files, and still don't need Xilinx to get all the binaries, as long as they don't modify their hardware optimizations.
Did I get the gist of it?