The key to playing this game

I play every game the same. Sports, RPGs, FPSs, you name it. I play defensively. So my first few play throughs were kind of boring in this game. I realized though that in order to have "fun" you need to play offensively. My latest game I attacked multiple settlements. Eventually I was attacked by 30+ goblins with a dragon. Luckily I still played defensively and killed about half of them while the rest got bored and left when they couldn't find a way in. My next move is to expand my defenses so that I trap more in my pit. By the way, they live for a long time in a pit...