If you are looking for a vicious military it's hard to beat turning a load of legendary miners into a military squad. The only downside is you will have to take them off their civilian mining duties to avoid wardrobe malfunctions. Give them some nice masterwork steel picks and a full suit of good armor, either steel or candy and they will tear through just about anything. It's preferable to let them at least train up their dodging a bit before sending them in against hardened targets like inorganic forgotten beasts made of rock etc. Dodging is a very important skill if you are facing creatures that can one hit cripple dwarves in full armor. Picks are the best all around native weapon a dwarf can wield.
Assuming you have access to either goblinite or traders, then train some mace dwarves and put some effort into looking for morning stars. They are absolutely devastating weapons that will seriously outperform whips. It doesn't really matter which metal they are made of but if I remember properly the copper and bronze ones might have had a slight edge. Higher quality versions are preferable but not necissary. Morning stars are large heavy weapons with high velocity multipliers. They cause absolutely devastating wounds that generally involve internal organ and bone injuries on par with a war hammer on top of severed nerves and arteries from the spikes. Think of morning star wielding dwarves as upgraded hammer dwarves as far as deployment goes. Like hammer dwarves they will make fast work of any opponent that is capable of feeling pain and which has bones to break. They will tear through armor like it is butter. Just keep them away from inorganic opponents incapable of feeling pain. Unlike hammer dwarves they can eventually sever limbs, but it takes forever.
If you have a squad or two of legendary pick axe and morning star users they will rip through just about anything. You might want to add a handful of candy outfitted axelords specifically to deal with things like giant husks, bronze colossi and inorganic forgotten beasts made of stuff like steel. Pick axes are still quite capable of taking off limbs, heads and or bisecting enemies like husks, but the smaller contact area means they tend to do it a little more slowly than axes particularly when it comes to giant sized opponents.
When it comes to non-conventional defense techniques they are only limited by your imagination. Some favorites of mine include dragon pill boxes, syndrome covered weapons, and all manner of magma powered mayhem.