1. Groups and Arrays--need to be able group items and array them, in linear and radial fashions.
2. Rectilinear/rectangular lights--for neon, accent stripes, coves, etc.
Thanks for your requests, cbarch - they have been mentioned by other users but it can't hurt to remind the developers about them (Since you are not a licensed user, your ideas would no longer be visible for you if I were to move them to the Wish List
section, so I'll have to leave your requests here).
3. Color Change LED lights--how to set these up in Lumion?
It is currently not possible to animate the light properties.