I just observed another thing:
When you browse to a device on the firmware selector - for a stable release, it offers you the file at the downloads site (i.e. including LuCI). But, the list of packages shown above the link doesn't include LuCI. You have to press "Request Build" to get an image with the packages listed (i.e. doesn't list LuCI).
Those familiar with OpenWrt might observe that instantly, others might be confused. Just FYI.