Two color requests:
Only 5 color choices in Canvas is a bit weak. A color picker would be awesome or at least all the HTML-named colors. You have this for connectors already.
Allow me to assign a default color for a given step block so that every time I add a code block it’s blue for example or whatever color I want it. This one is probably not that impactful because if steps are blocked only the outside one is the color… unless you would outline or shade steps contained in the block.