Fist Impressions - Book Covers!

Fist Impressions - Book Covers!

Been struggling for weeks now to come up with a good cover for my novel "Love, Sex, and Understanding the Universe." If this had been anything but seriously daunting, my book would have been published already. I admit, I'm a slow learner. Not slow as in dull witted, but slow as in it takes me a while to process, assimilate and digest info that requires an important creative output on my end. I've been doing a whole lot of learning and digesting, and have found some interesting and useful bits of info and advice.
A book's cover is of utmost consequence - it's that all important first impression. This is especially true in today's internet world of massive, quick, and ever-evolving information. In a book store or library, once you've bothered to pull a book off the shelf, chances are you're going to look at the blurb on the back, or read the first paragraph, if the cover is anything less than repulsive. On the internet,  people make split second decisions to move on if their attention is not immediately sparked by the initial image they encounter.
One of the great things about e-publishing is that one can change one's cover easily and relatively quickly if a cover doesn't seem to be capturing an audience. In fact this convenience has demonstrated quite clearly how much difference a good cover can make. I read of a woman whose first book wasn't selling so well even though those who bought it gave it great reviews. She came up with a much better cover and her sales exploded.
With e-publishing size matters. Covers on e-books are only virtual and most often seen in the size of a thumb nail. An author's graphics have to be big enough to be clear in that size. Same with the title. Extra long tittles, like the working title I've had for my second - soon to be finished - novel "Bonita Verses Ivan Rastaman and the Monkey-Go-Round," end up needing smaller font sizes to fit, and thus become illegible. Which is why I've decided to go back to my original title, "The Man with the Camera."
Color is an issue too because many e-readers show the cover only in black and white. The first option I tried for "Love, Sex, and Understanding the Universe" had a black silhouette on a blue background; the effect was pretty cool in color but didn't work at all in black and white.
Some other useful advice on creating a cover, that I discovered, includes:
Don't depict some profound aspect about your story that isn't going to mean anything to someone who hasn't read it yet.
Figure out what feelings your book is meant to provoke and create a cover that will provoke the same feelings. You can do this by exploring what your book's themes are.
Sex sells, so if you have a lot of sex in your story use it on your cover. Duh; but someone did have to point this out to me. Well I said I was a little slow.
Don't bring your potential reader down. Another thing someone had to point out to me. I had chosen an image of  a sexy guy on a bed looking distressed. Yeah, my character is frustrated a lot, but I don't want those considering downloading my book to think it's a sad story when it's actually quite uplifting.
Anything else anyone reading this would like to add, I'd greatly appreciate it. I'm still working on that cover.