The developers of data-star.dev are working on something interesting they call "Rocket", but it's currently a WiP and hidden behind a paywall so I can't really compare it to Lit. Lit is great though, used it myself a few times (e.g. github.com/romshark/demo-islands). But I still think there's a learning curve to Lit. Better than raw vanilla JS custom elements API, but still not as simple as it could be.