I would disagree that senators and congressmen are just vote messengers. They run on active platforms, respond to changes in their constituencies (hopefully), deal with new issues as they arise.
Electors literally just ferry the states vote to Washington, that's it and job done. Representatives continually represent the will of their constituents through multiple years, or at least that's what they are supposed to do.
They're still appointed representatives of the state, though. States vote in the election, per the Constitution.
I'd love to ditch the EC, but it does exist, and the electors are representatives. This isn't complicated at all, and I'm not sure why this is personal to you.