You're fine at that room size. I've recently acquired a new home and gave up my much larger room. The room I'm in now is actually just slightly smaller than yours. I feared I'd not experience as good a soundstage, but I'm happy to report that wasn't the case. In some respects having a smaller room I've found the sound is less room dependent, and the overall experience is more intimate than I ever imagined possible. I experimented with long wall vs short wall placement, and chose long wall to give me greater listening distance. Speaker interactions with the room have been far less on the long wall as well.
enjoy!
enjoy!