They could have committed a little more to the premise without making it constantly dark. Maybe a couple dark episodes in big two parters and season ending arcs and such. But they could have, say, not put a quarter of the episodes in the holodeck at the same time they're supposedly conserving power. Or gone through phases of greater power conservation policy, or shown somebody other than Paris temporarily assigned to a department they don't like working in out of necessity. Or after some tough battle make them land and do manual repairs they'd normally have to go to a starbase for. This wouldn't have made the show dark, it just would have made it seem like they actually were alone roughing it.
And they could have maybe had a dark season finale then balanced it out with a couple comedy eps.