The importance of a cover letter depends on the country and culture you are referring to, and of course, in some countries, they are positively frowned upon as pretentious. A cover letter can equally damage the effect your CV can otherwise create...forget that, at your peril. If, after looking at your CV, an employer wants further information, they will contact you, and you will have a chance to mould the information you provide according to their questions. This is better, imo, than wasting their time reading your assumptions on what they want to know and what, thanks to the AIDA formula, they have already read 30 times that day.

I dare not even think about what score that is on the index.