It is simple to change the system, just as soon as people stop focusing on the hardest parts, Astoria Bob.

When voting for reform-minded candidates at the local level, we can breach the dams of the duopoly where the dams are indeed weakest.

At the local level, we need to start voting for candidates that want full representation. Only pure proportional voting delivers, and at the local level we do not need to worry about electing 20 different parties.

It is all about the focus. When you believe it is all hard, then you will not do anything to get the liberty you deeply desire. Yet establishing change is easy when you know where the weakest spot is (which is well-guarded by both parties because they know exactly what to do to keep the voters in their places).

Once change has occurred at the local level, the foundation of the nation got changed, and the top automatically follows (but the parties may put up a fight); the two parties love their power (and the ones behind them benefiting from our having just two parties love it too; the two parties and their beneficiaries are stronger when the voters are weaker like we are here).