I don't think my typical selection is on this list, that being security. I make my fortresses just that, fortresses. I spend a long time overdesigning aspects of my fortress that are insignifcant and ultimately boring in the long run. I will say that I have never had my security fail, ever. I also have boring forts by comparison.
I'm also in the security camp, but chose military since it is my #2.
Efficiency, happiness, wealth ... all are impacted by the efforts to make the fortress a military stronghold.
The time planning this is where I get my enjoyment, excitement comes when trying to get the caravans inside alive.
this too, i almost forgot.
i plan to have hatches for every stairway and doors for every hall leading away from a stairway. My stairs are 2x2 and hallways are 2 tiles wide so i can always lock down any section of my fort should the need arise. This is essential to help me survive against in-fort animation of undead from the evil biome and also slows down forgotten beasts that manage to get in by alot.
All entrances to my fort are connected by hatches in the current design, including caverns so i can simply forbid hatches instantly should a threat arise instead of needing to pull any levers. My trade depot is in a sealed air lock that i only connect to my fort once im sure its secure. I have various forgotten beast traps ready, most of them being a air-lock to store beasts as fresh food for when my fort is hungry, or if its awaiting weaponization. Beasts deemed too dangerous to live, or just a hassle to kill, but not so strong that it could be weaponized, are caved-in by the trap design in my sig.