Hey, thanks for giving the game a go. If your raided as long as one person on night watch you wont get a strike It seems you were unfortunate in terms of rng and admittedly the game can reach doom state.
Heavy shelling is a difficult hurdle on your first playthrough and occurs around the start of the game, try to get tunnels dug using 2 men, it may be more risky but you free up an extra man. I always went for 3 only if I was gonna get a strike by the next day.
Through playing the game I tried to get players to find themselves having to prioritize the bureaucracy from their generals. Come at the game from the frame of mind that your there to appease your superiors, and not to increase that win percentage and you'll find yourself reaching day 15-20.
The strategy is about people management, a trickery task then people think.
In terms of balance I admit it probably needs more fine tuning I worked on this game for only 3days and there was only so much time to work on balance.
Once again, thanks for giving the game a go :)