Coalition governments work better than single political parties in many ways. Lets take a look at Germany, every political party is involved and has a vote in every major deciding matter that takes place there. In the US its very similar, but there is a unwillingness to cooperate from both sides. Other than that, coalitions governments work better at solving every issue or problem concerning its citizens.
There are disputes between the parties of coalition govt.
In single party govt it is fee to take its decision. When there are more parties every party will want other parties to obey its decision and it will be resulting in a great dispute among them and they will not be able torun the country.
Bringing in a coalition Government in place of our current standing political parties would destroy the US and the Amendments placed to us by our fore-fathers. This would violate our rights to speak out and stand our ground and cause an uprising in hate crimes and riots.
The US has always been able to Vote based on actions and proceedings by it's government. Having a coalition government and over ruling citizens rights to vote and imput in matters to them is infringing on all rights bestowed to us.