Combat is certainly possible. Like in classic Star Trek, there's combat. It's just that it's not the only thing happening, and the Enterprise isn't a combat-only starship.
A lot of the combat and conflict in this game would have to revolve around the idea of stealth. It's more like submarine battles than ships of the line slugging it out: can you figure out where the other ship is? What if they do a microwarp and pop up somewhere else? It doesn't seem like combat should happen at close range, like in most space ship combat games. It seems like it'd be more fun to sneak around an asteroid field trying to lock in your enemies without being exposed yourself.
Turn off your cooling vents to keep your ship from being noticed in infra-red. Use cold-gas thrusters instead of the much more efficient plasma thrusters. Get information about where the enemies will patrol, or where their stations are. Hack their systems before you even try to fire on them. Establish a laser connection to a turncoat, but don't get spotted...
One advantage of this is simulation speed. Because the other ship is not close enough to render on-camera, we can use a variety of shortcuts. We don't have to do things like real-time deformations, calculating crew injuries, precision AI piloting, etc: those only have to be done to ships in your fleet, ships nearby enough to see them. Therefore, we could do big battles with hundreds of huge ships - since nearly all of the ships can be displayed as schematics or icons instead of simulated in full detail.