The sales letter format should emphasize key points while maintaining simplicity. Do not repel the customers or clients. Have normal spacing between lines and the contents just right so that the reader does not feel over_burdened reading your letter. Get the reader to feel as if he is invaluable to you and your company. The pronoun "you" in place of "we" instills a sense of warmth in the reader, drawing them closer to your business.
Of course, you will eventually realize that even if you do not get that frenzy over the cover letter format, you will still have to pick one template to start on among many choices. Thus, it pays to know some essential points that will help in making a good cover letter.