It might even make more sense to just use fonts for the icons and leave SVG out of it entirely. I'm referring to the OpenType COLR/CPAL tables Microsoft is pushing:
I was looking for a similar solution recently, and came across Stackicons[0], basically icon fonts with multiple color layers, essentially what Microsoft is proposing.
But there's a huge flaw with the whole approach: you can't have color gradients. Of course you can still emulate gradients by using lots of layers, but it's going to look like crap when you increase the resolution.
