Yes, I like the Berlusconi parallel as well. And yes, the Donald hasn't proposed a single structural change to the US constitution or democracy. That, it strikes me is yet another fundamental aspect of making one a fascist in whichever century, the destruction of a constitutional democracy. Ironically, IIRC the Italian post-fascists have called at one time or another for the direct election of the Presidency. It would be funny if the Donald joined the direct election movement in the US. I could see him calling the electoral college a bunch of low energy losers.
Given Trump and his supporters open disdain for the law or party process (except when its to their benefit, of course), I've got a sneaking suspicion that Donald had remained quiet about any desire to restructure government as a deliberate choice. He wouldn't want to open himself up to insurrection charges or anything like that. I wouldn't bet that we wouldn't see a Trump Administration ignoring laws it didn't like.