I agree with @aturon that formalizing a 24-hour comment period for “easy RFCs” may defeat the purpose of the RFC process (gaining feedback). I also agree that this seems very subteam-specific as they will likely quickly develop an opinion on whether it’s a quick RFC or not. The only part I’d change is that I’d prefer to close the RFC entirely instead of insta-merge (but commenting saying an implementation is welcome). Now on the other hand if a PR is opened and gains lots of feedback about the design, I think it’s safe to ask explicitly for an RFC to get broader consensus.
An example to me of an RFC that is minor is RFC 1123, and I’d be fine just closing and saying an implementation would be more than welcome.