Hillary should have chosen Bernie as her VP, maybe it would have brought the Bernie or nothings back in. I think Bernie was put at a greater disadvantage (besides being an outsider/recent convert) by the tactics of the DNC and Clinton campaign, as well as a lack of media coverage, but Hillary likely would have won the primaries without it.
The biggest mistake was losing many of the Bernie voters. The emails leaks/DNC scandal might have been the deal breaker, and those measures weren't even necessary for Clinton's primary win. Nevertheless, it was a chalenge for Hillary to win over anti-establishment types that liked Bernie. So it still might not have mattered, without Bernie they might have still voted anti-Clinton. Republican districts are just fucked with idiots.