I try my best to avoid cage traps and the like, unless I have some
specific gauntlet I want them to run or I want to seek
revenge on certain individuals, so I might be able to offer some advice.
My current fort, Horncrypts is in it's 82nd year, so whatever I'm doing works for me, but do take it with a grain of salt, because there have been many deaths.
When I first started out, I set up two squads that constantly trained near the entrance.
Once they graduated to real soldiers, I set up a patrol on the long path winding it's way up the mountain to my entrance.
Along this path there are a few tunnels that go in and out of the mountain, before reaching the summit.
This is in a region that always snows, the advantage being that I can "see" the goblins track snow into the tunnels, before they are actually revealed.
I can better prepare for them this way.
A few decades later, my dwarves had finally set up shop in the first and second cavern layer.
So, I then switched the patrols to the halls that lead down to the first cavern layer where the beginning of my fortress resides.
I have a constant patrol of soldiers that patrol the upper halls, I have another patrol for the inner ramparts leading down to the second cavern layer and a third squad that is constantly training where the fort exits to the third cavern layer. These areas are not for civilians.
None of this really seems like a big deal and I don't think it's anything special, but I think the real secret is to
not care if your dwarves die in battle.
This isn't to be confused with trying to kill them. I use the hall's corners to my advantage, back doors to mop up runners and positions the xbow squad in the best spots to pick off any attackers in melee with the Hammer or Axe squads.
My dwarves dream of death in battle and I give them that.
Focusing on that, I have never set up a sculpture garden, meeting hall, etc. This creates a lot of "passing acquaintances" and if done right, their only friends are the gods.
My only weak point right now is the mayor. She's had 30 kids and I've tagged each of them with nicknames, so they are never thrown into the military.
A few of her kids have found death, but luckily the amount of children she has had mitigates the damage done by any "oops".
She came married in a migration, but if you can avoid any marriages, that is best.
Thankfully her husband died recently, placed in a nondescript tomb in the crypts to be forgotten.
When I first started playing DF it was hard not to not get attached to certain dwarves and I still find myself tagging a few that have just done awesome things. Growing fond of a few is fine, just as long as you don't panic at the thought of losing
that one at the expense of many.
As an example, Catten, Hammer Dwarf, on patrol was surrounded by two packs of goblins, fighting them on the edge of a cliff. After taking out a few she was slammed into and knocked off the edge to land in the snow below.
The goblins would have rained arrows down on her, but the rest of her squad showed up, drawing their fire.
She picked herself up and made her way back up the mountain path as her mates cut and smashed the goblins that had attacked their comrade.
The goblins ran down the path as Catten met them coming back up, smashing the remaining greenskins.
She took joy in slaughter lately. She really doesn't care about anything anymore.When her squad leader died, I promoted her to Militia Captain of the Hammer Squad.
She earned it, always first on the scene and emerging out of the miasma victorious on countless occasions.
A few years later, Catten was guarding the obsidian bridge over the magma in the third cavern layer with her squad.
She and her entire squad, but one, was killed by a forgotten beast's dust cloud.
Heroes rise and fall in dwarf fortress.
There's always more to replace 'em.