With the soon to be stabilitized associated constants, I wonder if this project would greatly benefit for rewriting some of the Vec code to use them.
This would allow for Vec's to be not limited to 2,3,4, and allow the code to be more readable by having less macros around it. I am sure there are many other quick wins we could get from them on this project but these are the first couple that came to mind.
(unsure if this project is still maintained)