Improving Academic Presentation Style

I give a lot of talks, and I've been trying to improve my presentation style, but I'm not sure how to do it in the context of my field. I am in a fairly quantitative science. I have to give presentations where I present results; I am 'selling' the result to the audience, but not in the same way, I think, that one would sell a product, or an idea, or a concept. I'm attempting to convince them that it's right, and that I was diligent in pursuing the result.

One common technique is to simply overwhelm the audience with lots of facts and charts and bullet points. Obviously this is a bad idea -- but on the other hand, if you don't give enough 'serious-looking' plots, you run the risk of being dismissed by members of the audience.

So how do I strike a balance? How do I keep my presentations in the manner of a good narrative, with appropriate display methods, when constrained by an audience that has a certain expectation of a larger number of quantitative figures and numbers?