I am trying to achieve a galactic expanding start cluster and nebula. I have a bit working but it seems that it is difficult to get even light throughout. I am aware of postings like How to create a Nebula in Cycles? but they don't apply to the following details.
I would especially like the expanding Stars (Particle System Objects with emissions) to light an expanding gas cloud, driver by a central force that should expand it. I cannot use lights if I create too many nebula, especially with light limits in Eevee. At the moment I have only a central Point light that is insufficient to light the "smoke" from the nebula.
I have both a central force and also Normal Initial Velocities on the Geometry and Inflow objects. Yet I see minimal, faint expansion, while I would like the gas shell to expand to approximately follow the stars that would also light it.
It seems that the Inflow object is not "adding gas" as it should. Does Volume Emission even work?
I am also using a spherical collision object to prevent gas expansion to the Domain Cube. Is there some way to instead use an Outflow Sphere for a superior effect?
I share my attempt: 
