but that issue is separate from what's wrong with the Senate.

I'm not sure that it is. We have a bicameral legislature, you can't really separate them completely. Together they are "Congress".

I think the Senate would be fine as it is if we actually had a proportionate House of Reps.

And maybe the Senate shouldn't be the "upper house" as I think "The People's House" (in this scenario, actually proportionate) should be considered more important.

But I think calling for the abolishment of the Senate entirely is misguided. I like the idea of a federation of states, each with a degree of autonomy. And given the nature of the US being a nation of immigrants (and it's sheer size), I think it fits our culture very well.