tl;dr: It is sadly not the most efficient encoding (and they missed an opportunity to make it actually base41, which could have been URL safe) -- as defined it only needs 41 characters (as 41^3 > 2^16).
The RFC is also not standards track, it's just "Category: Informational".
I think a better approach is to understand there are many circumstances where different sets of characters make sense for encoding data. There's no need to write an RFC, instead define a custom alphabet for them, using something like base-x[1].
tl;dr: It is sadly not the most efficient encoding (and they missed an opportunity to make it actually base41, which could have been URL safe) -- as defined it only needs 41 characters (as 41^3 > 2^16).
The RFC is also not standards track, it's just "Category: Informational".
I think a better approach is to understand there are many circumstances where different sets of characters make sense for encoding data. There's no need to write an RFC, instead define a custom alphabet for them, using something like base-x[1].
[1]: https://github.com/cryptocoinjs/base-x