I've been using twinmotion recently, became my favourite application really...
so in comparison with lumion, here is what I think TM is falling short:
1- characters: TM characters look more cartoonish while on lumion, they look like they were scanned or something.
2- Vegetation: same point
3- Painting grass: I think we should have an option where u select for instance a plane, or a some object, and u just click fill... instead of paiting through long distances.
4- Lights: an option to choose if it should be ignored by the light or not.