I actually think the problems with the US are limited to a few problems that result in perverse incentives. A few things that I think could help remove dysfunction from our system:

-Increased voter involvement (easier said than done). This is probably the most difficult to change to implement since it's such a cultural phenomenon. It would help to have increased access to quality news sources that actually do real reporting rather than the mass media which, at this point, is little more than a mouthpiece for their preferred political friends. Instilling Americans with the idea that yes, they can actually change the government, would also be helpful. No matter what changes we make in the system it ultimately won't serve us if we fail to take a real interest in what the system does.

-Remove money from politics and make all elections publicly funded. This will hopefully reduce both the ability of private industry to influence politicians and the politicians' perceived need to be fundraising all the time, stealing time away from the work that's actually important (you know, governing the country). This would also prevent, by the way, outside groups from campaigning in any election - whether in coordination with candidates or not (I'm looking at you, Citizens United).

-Reform how voting districts are drawn. I'll admit that I don't have an ideas on how to do this; it seems like any potential solution I can come up with is open to the same abuses the current system is. One potential way to do this would be to have representatives chosen by county/parish, though a 1:1 conversion wouldn't work as a quick look at Wikipedia says there are more than 3000 of these districts in the US. I'm not sure if there's an easily objective way to do geographically divide the US into voting districts, though perhaps changing our voting system could make it possible. Which leads me to...

-Reform the voting system. Replacing our current first-past-the-post system and replacing it with any of the myriad of proposed ideas would be a start. Ideally, the new system would make it easier for opposition party candidates outside of the traditional two parties to get involved. With respect to the issue above, this might also involve rethinking how we implement our proportional voting system. Rather than, for example, voting for representatives by geographical area, representatives could be voted on in state-wide elections, with the top X vote-getters earning spots (where X is how many representatives a state is assigned). There are obvious issues with this (e.g., one candidate receiving the majority of the votes by virtue of being extremely popular, leaving the remaining spots to be filled with relatively unpopular candidates), but it's an alternative.

-Finally, institute hard term limits. This serves as a firm check against perpetual incumbancy. While I think it's important that our politicians be competent in their jobs, I think it's healthy for "fresh blood" to constantly be entering these institutions. I find it difficult, for example, for people born in the 1950s and 1960s to really understand how things like the internet work for most people. They simply don't have the cultural reference to be familiar with more recent issues, which obviously impacts how they vote on things related to these topics.

These are by no means excellent solutions to the problem, but they're the things I could come up with off the cuff. I think substantive election reform - whatever the implementation - must address issues related to campaign funding (specifically, removing or limiting the influence of wealthy outside influences), encouraging more extensive participation by both voters and alternative political candidates, limiting the length of time politicians can serve in office, and limiting the influence of political pressure in how the politicians themselves are elected. I'm sure there are a variety of ways to solve these problems, but as long as they're addressed in a meaningful way, I think we can greatly improve the system we currently have.