For obvious UX reasons we want to have the simplest and quickest registration process while maintaining adequate checks against abuse.

• fewest possible user tx. 1 or even 0
• shortest wait time possible before registration is valid (tokens assigned, user can use vote, use dapps, etc.)
• simple to implement
• upgradeable

It's quite possible I've been overthinking the whole registration process recently (!). Or maybe not, maybe registration is really at the heart of what is happening here and should be perfected rather than moving on quickly to what we can actually do with registered users. Who knows!? Either way I think it's worth considering alternative simpler-but-adequate solutions. One such solution could employ delegated registration validators.

• bootstrap validator set from users over some community karma level (10,000?) and who also accept the role
• user registrations are ACTIVE after 1/3 of validators support
• 1/3 of validator set can block registration
• protocol mints some tokens to pay validators or fee taken from registrants allocation
• add/remove registration validators by dao vote
• registrants make a registration request comment with their chosen address. once 1/3 of validators support it (they could sign off-chain or support on-chain) then registration is successful and tokens are assigned.