This is an excellent proposal @jdorfman, and it has actually been discussed in some of the Governance Readiness telcos. We knew the site to help to choose a license, and we were considering how we could reach something for governance.
The most similar approach is CommunityRule, where you can find templates and guidelines to prepare your governance model. As governance rules are usually very specific for projects, I find it quite hard to follow strict governance structures (as we may do for licenses). In this sense, CommunityRule templates help kickstart governance models.
The current approach for CommunityRule goes beyond defining governance models for Open Source software projects. Thus a potential line of work I see is to work on those specificities that could particularize the templates for Open Source. Maybe the next step for the Governance Readiness WG?