Here's a side-by-side, mono and a proportional typeface I edited for camelCase readability. It has a 1/3 space to the left of the caps. I call it VerdanaCamel:

https://twitter.com/efortis/status/1501988964198191113?s=20&...

The only cons I see is that it doesn't align to columns, but that should be a rendering feature on modern IDEs.