I have a set of related suggestions for changing the complexion of the national legislature. I am not wedded to any of them, but I think that they'd be interesting to discuss, so here goes:
1). Increase the number of Representatives in the House to 2,000. As someone's pointed out in comments around here, our current slate of Representatives are representing something like seven or eight times the constituents as the ones in 1791. Let's cut that down a bit; besides, it'll take the parties years to work out the new gerrymandering protocols.
2). Make DC a real, live state. No taxation without representation! For that matter, we've got a bunch of offshore islands that really need to have their status resolved once and for all.
3). Directly link the number of electors in Presidential elections to Congressional Districts; eliminate 'winner takes all' in EV contests. You want to win all of, say, NJ's EVs? Win every county. Don't feel like hitting every county in America while stumping? Don't come crying to me if you lose. Think that this will sharply increase the power of local political parties? Good, you're catching on.
I'd also personally add 4). Repeal the 17th Amendment and 5). Stop trying to regulate political ads and/or cash , but those are both fairly controversial positions to take. Besides, these three should be enough to start a debate.
PS: Yeah, I know, not a chance that #3 will be adopted - and not a good chance for #1 any time soon.