The Heroic Games Launcher is a fantastic community effort to bring the Epic Games Store to Linux and Heroic Games Launcher 1.9 builds upon the foundation to provide a better experience. Since Epic Games clearly still have zero interest in bringing their store to Linux officially, this is one of the best options that doesn't require messing with the Wine compatibility layer directly.
As a reminder: since Epic Games don't support Linux, all downloaded titles will use a compatibility layer like Wine.
Heroic 1.9 is now a lot faster. It has a cache of information stored and makes requests in the background, so the whole app should feel more responsive, which is very nice. There's a bit of a design refresh too with new colouring and the login screen now reflects that too. There's also a better tray icon too and a few UI tweaks.
Not all of it is style related though, there's new features too. You can select to have it start minimized, there's a playtime tracker (stored locally), a new game install flow to show a window with the options to install or import the game, running Heroic from a terminal will give more output to help debug issues, there's an AMD FSR toggle and Sharpness strength for Wine settings (although this needs a supported build of Wine to work) same with Resizable BAR for NVIDIA and there's also now Wine and Prefix information on the game page.