I didnt put the ability to put multiple suns/moons in the roadmap because it increases complexity a lot. I put it in the howto series because people want to know how, so I will guide the implementation in the video. The point on controlling the orbits individually is not that difficult, since the function to calculate the orbits are inside the BP_TheMoon and BP_TheSun, these blueprints can have different functions to calculate the orbits and be used setting the instances accordingly.
The complexity resides in the main raymarch material and the main blueprint, already expensives, where it will need to add more parameters to handle the additional directional lights and the ability to use the combination of each contributing light (like when two or more different suns are present in the sky) to the scattering effect at the clouds… it might also happen that too many suns may cause almost no shadowing at the cloud body reducing a lot the quality, since the overall beauty comes just for the shadowing part. The sky sphere material and its blueprint will also need to receive changes, thou quite easy.
As we can have a duplicate material just for this experiment, following the videos to add simultaneously another sun + moon is quite enough for the audience create their own material and be able to add more in the future using it as reference.
Overall, the roadmap is already filled with neat stuff and Id like to have a complete system before moving to specific implementations and in this case probably replicating more blueprints.