I'm a solo dev working on a space RTS game set in the Milky Way galaxy, containing currently known stars and exoplanets with their real characteristics, the remaining stars are procedurally generated.
In the online mode, all players are in the same universe, and the world is persistent. You compete with other players to take back the Solar System and end your exile. Players can always retreat to the periphery to regain strength and rebuild their fleets as needed.
It also includes an procedural spaceship generator that allows creating your own spaceship designs. Spaceships visuals don't change their stats. This way players won't have to use spaceships they don't like due to superior stats.
Spaceships keep operating even when the player is offline: production spaceships keep harvesting resources, and combat spaceships automatically engage invading spaceships. To allow players to mount proper defenses against large attacks, they can build disruptors to slow down travel from enemies to their systems for up to 24 hours.
Now it can be played in the browser: