We are actually working on this! Just because we did some small fixes doesn't mean we aren't working on something bigger :). The current app is a full isomorphic SPA with React + Redux. It's a beast, and around 80% of the code is completely unnecessary on the client. Our initial approach was little tweaks and performance wins like this, but those are diminishing returns with a JS payload size so large.

Next week we are rolling our our new property detail page for Rent.com that is mostly server-rendered with a few interactive React components injected and hydrated on demand as you scroll. It brings the app bundle size down from about 1.5MB (yikes!) to around 140kb. It's been a huge, long effort and is a completely new app architecture. It of course increases our score way more than just 17 points :)