Seconded. I got QML running on my pi using EGL (fullscreen without X) and love it.
QML is actually pretty awesome, I got into it through KDE/Plasma widget development. I think it should be possible to get newest JS working using Babel in your build pipeline. I think it makes a LOT of sense in cases where you develop a UI and can't effort to embed webkit/chrome.
ES6 in Qt 5.12
it's all the way to ES7 in 5.12
Wow, I just checked it, and it looks awesome! I'm very exited about the next Qt 5.12. Thank you for letting me know.