What behaviour detrimental to the system does curation cause when it's too low?
Defund bidbots? Curation rewards aren't anything other than rent seeking. It's because of obscene curation rewards that curation has no relation whatsoever to content quality. Content is nothing more than a vector for profiteering for curators.
Eliminate curation rewards completely. Circle jerks and masturbatory self votes can be dealt with in different ways.