How does amending a document that is ignored help anything? A real new convention would try to dot all the eyes and cross all the teas and would look like the European "Constitution" with hundreds or thousands of pages.
The most important one restores a senate of the states, through repeal of the 17th Amendment.
His amendment proposals are structural. They cannot be gotten around through "living and breathing" nonsense.
Levin's Liberty Amendments, a Summary