"Clumsy", perhaps. Polemics have never been a conservative strength.
But if the conservative message -- individual liberty, self-reliance, free markets, freedom of religion, et al -- is also perceived as "ignorant", "simplistic" and "oppressive", there is something seriously deficient within the audience.
Failure of communication is often a fault of the communicator. In this case it definitely is. The message is great (actually exactly the same message that the UK Conservatives presently claim to be pushing), but the way it's told isn't. It's not getting through. I'd love to do a European poll on what phrases come to mind when someone says 'conservative American'. I'm sure none of your descriptors - 'individual liberty, self-reliance, free markets, freedom of religion' will appear.