When we have solved this particular problem, we need to have a chat about Kate Bush. Not really about music, but I find the main image on this page a good example. The file is 47 kilobytes. Personally, I never use files that size on a web page. But you should use bigger files than this only if you need a bigger image (filling more screen) or higher quality. Your Smiling Eyes cover image alone is 7 times as big.