The only problem is electing the parties. Which parties will have the privilege to talk at the bitcoin parliament, and how many people from each party. This might be a tough problem to solve. But this is just a crazy idea, isn't it?
I consider this problem not only tough, but impossible to solve in a satisfying way. There are only three possibilities:
1) Vote by hashrate - so miners would be the powerful elite that elects the "Parliament";
2) Proof of stake - that would not only be a Plutarchy but give excessive power to bank-like actors (exchanges and payment processors)
3) Sacrifying anonymity/privacy and link the addresses to real identities, which is one of the core values of the community and would never gain approval by the majority of the users.
Vote by hashrate is already happening, with dissatisfying results and empowering only a very small elite. Proof of stake voting has been implemented in some altcoins (DPOS, NXT) but I consider it a no-go that banks have formally the most power on the election of a "politic" institution.