For the record, I am all for inclusiveness and think it is good to put as many implementations on the site as possible. What I want to avoid is the misuse of the RnRS labels. The RnRS labels should have a meaning, especially on any web site that aims to promote “Scheme”.
I agree. For example, none of the "RnRS" tags should be used to describe a Scheme that does not have full tail-call elimination. Not having that means that many programs written in Scheme simply won't work.
Using a numeric score to evaluate Schemes based on features beyond the standard seems fine, but we shouldn't use it for features that are supposed to be part of the language.