Yes please - feedback is welcome!
Part of my philosophy is that one’s interpretation of data generated by someone else can never be perfect. A mute, as you point out, can mean things other than bot. So let’s say that some day people start using reports (NIP 56), labels (NIP 32), or some other method to flag bots that is less ambiguous and more specific. It will be relatively straightforward to feed that new source of data into GrapeRank, give it more weight than mutes in calculation of the “not-a-bot” score, and improve the ability of your grapevine to differentiate bots from not-bots. This ability to consume data and turn it into useful scores will in turn create a demand for greater variety of methods to generate greater variety of types of data.
I hope that makes sense!