I don't understand how [1] makes your argument... Sure economy is important, but the question is, do the policies differ? Like, it's probably 99% important to voters that they elect a "natural-born American" but if both candidates fulfill this condition, it makes 0% of the decision to whom they will vote for.
I perceived (and I thought many other people did also) as Sanders running more on economic issues (equality, taxes, etc) and Hillary running more on social justice issues (deplorables, "woman card", equal pay, immigration, racial justice, etc)