As you like online tools to play with, here’s another one which can provide some highly technical insights into your website: the Google PageSpeed Insights Tool. This has been updated to show you more about the mobile performance of your website, and provides recommendations for speeding it up. Admittedly, these are really technical, but if you’re on good terms with your website developers, you could do worse than suggesting they comment on what Google’s suggesting. Remember, page speed is a factor in your ranking in the Google results now, so it’s worth improving if you can.