Guess who has the most boring night ever? I tried to make a UN Parliamentary Assembly (upper house, if you will) based on the One Country, One Vote principle and using rough international parties based on the EU parliament. Each country sends one representative. This involved a lot of guesstimates and probably too much time reading on the internal politics of, say, Guyana. Going by several rules of thumb and grouping parties on rather flimsly principles, here is the Result.
United Earth Party (Conservatives and various democratic right-wing): 39 seats
Socialist International (Social-Democrats and various democratic left-wing): 30 seats
Progressive-Liberal Alliance (what it says in the tin, plus several 'broad' democratic coalitions): 25 seats
Revolutionary Left (Marxist-Leninist countries, plus several far left nations like Venezuela, Angola, etc.): 12
Global Green Party (Austria, Latvia, Vanatu and (stretch) Costa Rica. Mostly here because I really like the Greens): 4
Independents (single-party states, absolute monarchies, non-partisan democracies, military juntas, many dominant party states, countries whose politics are just WTF, nations in civil war, North Korea, Russia and China): 83
This parliament would be an absolute nightmare to work with, and any majority would involve working with tin-pot dictatorships and countless non-partisan Pacific nations. Can you imagine, say, the Socialists trying to win the swing country of Marshall Islands?
However, there's something worse. The Lower House (officially called the People's Assembly, unofficially, the Madhouse). Using a good ol' one person, one vote system (not those weighed by GDP or that kind of fucking bullshit), and 1 representative by 1 million people, the People's Assembly of the United Nations counts as MPs, as of 2015:
Yeah... anyone willing to map that parliament? I value my own sanity too much for that...
(made with:
https://tools.wmflabs.org/parliamentdiagram/parliamentinputform.html)