I brought a fortress out of a tratrum spiral. By the time I had 50 population, I'd had 25 deaths. An entire third of my population. Dwarves weren't happy and I didn't have enough coffins. The King had shown up really early because I accidentally struck HFS and he was trantrumming, picking fights with [read: killing] children. My armorer had entered a mood right after striking HFS and made a set of greaves out of the stuff, which boosted my fortress to TEN TIMES what it had been worth, attracting sieges WAY too early. A goblin siege had just claimed several champion wrestlers at once, so their spouses and friends were sad. It was a map without wood, so this early in the game, after the huge greaves-related immigrant wave, I was WAY behind on beds, too. Lastly, I was out, out of alcohol. Limited ore and no wood for barrels.
I engraved my dining room and placed a few more tables. Every artifact I could build (hatch covers, tables, chairs, floodgates, grates) was placed in a high-volume traffic area. Several of my unhappier dwarves got drafted to the Fortress Guard. That gives them an unhappy thought, but also a happy thought to counter. Then they get to spar, which is a strong happy thought. Once they were happier, the slightly unhappy dismissed from the guard thought isn't a problem.
The tantrums stopped, but I lost he king to a berserk rage. I wasn't upset, though. I really didn't want him in the first place and I didn't have the means to build him nice rooms yet.