Something I'd love to see in the future of Roll20 is a mechanic for different types of light to be added to the game based around whatever token you have as the source. Sunlight, torch-light, light from a hooded lantern, the glow of a phosphorescent mushroom, etc each have different qualities. Also, it would be nice to have some kind of vision stat that was reactive to these qualities (such as low-light vision or darkvision). I'm sure you guys are working on it.