Ehhhm, just use solarized light if you need a good light theme...

I have about 1500 lines in my VSCode settings.json dedicated to custom syntax highlighting and text decorations (this could be trimmed, some is from before the days of semantic highlighting), but regardless, the amount of differentiation I can achieve with this is simply not possible on a light background. I've tried! (Solarized light is a nice theme though)