I think your ceilings for Trump are too low.
A lot of things can happen between now and November.
Another ISIS attack on home soil and those maps will go a dark shade of blue.
I think any estimation of Trump's ceiling/floor has to include a caveat of "assuming nothing earth-shattering changes". Otherwise the whole exercise if pointless. For Trump, Rubio, Clinton, or Sanders, you can produce a "wins/loses everything" with just a few plausible but less-than likely changes.
For example, a strong, massively-funded third-party run from the right hands the election to the D candidate. And similarly, a massive economic crash (or terror attack across the Mexican border) could hand it to Trump. But while such things are possible, they're not likely, and taking them into consideration doesn't actually tell us anything.
