Regarding "5. Use gradients and SVGs instead of images". In a sense this can slow down performance because it requires more effort for the browser to render these, especially gradients. I'm not saying don't use these, because I certainly use them and am a big fan of SVGs, but technically (at least for the rendering process) they are more browser intensive than images. Of course there is the tradeoff that images need to be downloaded and are therefore perceptively take longer to load.
Regarding "5. Use gradients and SVGs instead of images". In a sense this can slow down performance because it requires more effort for the browser to render these, especially gradients. I'm not saying don't use these, because I certainly use them and am a big fan of SVGs, but technically (at least for the rendering process) they are more browser intensive than images. Of course there is the tradeoff that images need to be downloaded and are therefore perceptively take longer to load.
+1