CommonMark compatibility could really help. Those quirks were really painful.

I recently tried building out some financial reports using Observable but found myself really stuck on the quirks around HTML and Markdown. It felt like it would have been a great tool if I could just drop down into full HTML templates rather than having to mix in Markdown. Markdown is great for initial prototyping but once I needed to customize some tables outside what the stock controls allowed for it became really impossible. Ultimately I had to scrap the project and move over to Gatsby which allowed for better template control. Though it’s certainly a lot heavier of an option.

"New contributors" in the changelog is a nice touch.