One can copy ligatures between fonts: https://github.com/ToxicFrog/Ligaturizer

That would remove my primary objection to Input. Seeing a broken arrow -> is ground glass in my eye; other font subtleties are a sign to me I'm losing focus.

I could never understand why on Earth anyone would want to render two separate symbols as a single glyph in the source code, one of very few types of written material where every individual symbol actually matters.