I'm not quite so pessimistic as the OP. I think all the things listed will have a small but significant effect over time. The OP talks about "grinding away Clinton's support" but I think these things will grind away at Trump's support, especially now he seems to have lost the media thanks to the Trump Hotel fiasco.
But, yeah, if anything causes a sudden drop in his support it'll be the debates.
Unlike Hillary's support, Trumps supporters are REAL and actually believes in the candidate.
I guess I'm not a person, then. Please outline for me Trump's policies, I'd be curious as to why someone would support them.