polymer-cli "works" but it hasn't received a real commit for over 8 months, and issues are piling up quickly. It's not a good look.

Using es-dev-server would be a much better idea -- and it will give developers a much better idea of what they should actually use.

The very first page of lit-element's documentation links to https://github.com/PolymerLabs/start-lit-element which had its last commit 1 year ago and refers to polymer-cli.

Also, it would be graceful to have a link to open-wc from the documentation.

I think a section "Writing apps" would ideally link to open-wc, and summarise what's provided with npm init @open-wc.

Right now, lit-element is telling users to use an effectively abandoned repository to serve elements, an outdated "hello world" project and no mention of how to create a full app, which is most people's goals.