Are there too many "checks and balances" in the US political system?

[Nichlemn]

A lot of people like to play up "checks and balances" as being a great part of the US political system. But surely there can be such a thing as too much. I doubt anyone would support say, unanimity rule, or six chambers of a legislature.

As the states and federal system tend to be similar (most being bicameral with a veto that can be overruled by a 2/3 majority) I've lumped them together.