As you almost certainly know, copy is what sells.
That’s true in print, and it’s equally true on the web. A completely unstyled site with strong copy will sell infinitely more than a beautifully styled site with none. And since the average website is between 90 and 95% text, one leading expert wisely observes that “web design is ninety-five percent typography.”
So while you can be quite flexible with how you present other parts of your text, your body copy needs special care. Making your selling content difficult to read is like mumbling to your prospects. You might as well turn them away at the door.