I'd be f****d. Insurance companies seem to be low balling and fighting it is a lengthy process. I couldn't remotely afford a new P85 if my Dec 2012 P85 got totaled. Maybe I could find another used one, particularly now with the D's coming out, but odds are really good I'd just be unable to afford another Tesla. Being able to get one at all was a once in a lifetime situation for me.
I'd probably get something like a 3 year Volt or Leaf lease and wait for the Model 3.