NPR recently aired a story about an author who specializes in translating Star Wars movies into Shakespearean language. Along the way, he has managed to take one of the most hated characters of the franchise, the fawning, simple-minded, suspiciously accented JarJar Binks, and added unexpected depth and interest to him. We may never grow to love JarJar, but now, using a couple of Shakespeare’s common techniques, the aside to the audience and the clown or fool character used as a disguise, we can understand him better. This is an inspiring example of how to add shading and dimension to a character to enhance the interest of and connection to the reader.
Your characters may not actually have any other dimensions to add (i.e. they may just be that shallow) but you might reconsider their cause after seeing what a little extra detail work could do. I have known a few people who put on accents or goofy personas when they want to disarm others. I have seen the ploy be too successful as well, to the point that the actor cannot be taken seriously anymore. If this author is to be believed, that is exactly the case for JarJar and we should all be ashamed of ourselves for thinking worse of him. I reserve the right to wince anyway.