Just to be clear, you're referring to micro ATX mobos right? The heat is due to the components being closer together, not necessarily a design flaw of the platform itself.
Regardless whether or not I'm right about mATX referring to microATX mobos, I would first try to get a detailed picture of my components' running temps before considering adding to your cooling setup. Who knows, your CPU could be actually running at only 50C or even 40C under load? :P