I would consider it a mistake to ever rename Exporter::Tidy to Exporter - Exporter should never offer Exporter::Tidy semantics. Newer code should fail for absence of Exporter::Tidy on old platforms, not for lacking support of its semantics in the then current Exporter: simply installing Exporter::Tidy is much easier than replacing the entire Exporter package.

I'm also not saying Exporter::Tidy should support the Exporter features at all. It would be the sole responsibility of Exporter::Tidy::Compat to translate.

Looking at the list though, I'm wondering whether it would make any sense at all.. supporting some of them would obviously require modifications to the import() that would water down the whole thing. Limitations on what could be done without changing Exporter::Tidy's import() would be acceptable IMO, but "user visible" changes to the interface are not. On those grounds, consider my suggestion retracted.

Makeshifts last the longest.