Well, I've found that making animal people in Adventure Mode makes it ridiculously easy. Like, really.
So, I made an elephant seal axeman, and he starts with an iron halberd. This is in a rather small island world, a good amount of beasts, a few bandit camps here and there, some kobolds in one city's sewers.
End of my IRL day? Nothing left. Not a single trouble to this world. They just couldn't stop him. Anything human sized or smaller literally just couldn't break free whenever he used a chokehold, making them easily fall to the whole giant iron halberd thing, and anything else could just be dodged around until it was hacked to pieces, thanks to the fact that he moved as fast as any other creature.
Let's take something else into account here. An adult elephant seal man is 1,535,000 cm cubed. A fucking minotaur? 220,000. Trolls? 250,000. An adult human is 70,000. Like. Using something like this species just means you'll bowl over any other enemy, and I love it. Now, whenever one of my legit adventurers gets killed in a stupid, unfair way, as DF is wont to do, I just make one of these guys, and EVERYONE DIES.