I have proposed a rewrite of BIP-322 on the ML:

https://lists.linuxfoundation.org/pipermail/bitcoin-dev/2020-December/018313.html

Full text (also included in the ML post, but rendered here)

https://github.com/apoelstra/bips/blob/2020-12--bip322-overhaul/bip-0322.mediawiki