The new SEO tools are nice but since page speed is one of the most relevant aspects you should do something about slow loading.
Just a few examples of what Googles PageSpeedInsights tell me:
Eliminate render-blocking resources. Estimated savings: 4.19 s
Resources are blocking the first paint of your page. Consider delivering critical JS/CSS inline and deferring all non-critical JS/styles.
URL Size Potential Savings
/ik/_PbYZD3ye….js(use.typekit.net) 8 KB 780 ms
…scripts-compressed/common-526b9c5…-min.en-US.js(assets.squarespace.com) 424 KB 3,330 ms
…156…/site.css?&filterFeatures=false(static1.squarespace.com) 51 KB 1,380 ms
Can I do anything myself?