But your proposal doesn’t do that, as appealing to Dem Primary voters in, say, Ohio doesn’t necessarily mean a candidate would be more appealing to swing voters in that state. It’s possible the candidate who can win some support of at least a few traditionally conservative voters in Conneticut (for example) could be better equipped to win Ohio in the general, even over someone that won the primary there.
So in the end, you’re just making some members of the party more important than others using a similar flawed standard as what we have now.