Direction election of senators does not "concentrate power at the national level" somehow. We've been through this. It is a weird thing to believe, as if state legislatures are bastions of local control or something. Direct selection was not some sort of devious progressive plot to centralize power in Washington. Again, your beef with the 17th amendment is just weird...and can only be made by people unaware of how state government works (they are a cesspool of corruption).
House members are not selected at the "city level" somehow. That's just weird.
Correct on the filibuster, though.