and what key variations would 10 parties have to all be different from each other, pray-tell?
to often we are left with a majority senate/congress of 1 party, and a president of the other. the pres infinitely veto's everything, and nothing gets done for 4-6 years. depends what sides gets elections next that changes it.
even worse is if you get a tri-mono party government for a bit. they will pass everything they create, and instantly have their way without a fight. thats scary as well.
a house full of 6+ parties will never tie. and whatever party controls the white house will be forced to vote both ways on every other bill.
instead, as of now; we are stuck with a government that dosnt move
think about the budget bills we keep failing on right now. this is the main cause for its failure.