Recently I moved a medium sized site from a domain to another. During the migration the structure of the site (page name/page dependency) changes but site data does not change. I was advised to maintain an active old version of the site with 301 redirects to the new version (a 301 rule for each page that I move, keeping track of name changes.) Doing so will have the benefit of "SEO backward compatibility." By that I mean that Google will continue to index previously indexed URLs.
But that technique does not convince me, it's very time consuming to handle (I need to remap each page name/ parameter name) and I have to maintain the old infrastructure active potentially for months. Is this the state of the art or is there a better approach?