Due to a combination of a bug which makes cage traps impossible to escape from and the fact that they are insanely over powered to begin with, cage traps are a real game breaker. As it stands right now using nothing more than a log and a piece of stone, a completely unskilled dwarf can defeat a 1000 year old ancient dragon which has destroyed entire civilizations without even getting so much as his hair tussled. Give that same dwarf about ten minutes of time and you can set up a line of cage traps that will take out an entire cave dragon mounted goblin siege like it was nothing. Add some webs to it and the Lords of Hell and the Old Gods themselves are helpless in the face of a rickety cage made of sticks.
From a logistical stand point there is simply no point at all in using anything but cage traps to solve any and all enemy threats which is something that really needs to be changed. As it is right now a cage trap will radically outperform a weapons trap that took 10 times the resources to create and in some cases will even outperform an entire steel clad dwarven military that has taken years to train and equip.
Adding size or strength limits to what a cage trap can work on and fixing the bug that would allow beasts to escape from them would do a great deal to fix this problem as would massively increasing the cost and skill required to make them. Another option to make them more realistic would be to tweak pitting so that a hundred and fifty pound dwarf can't drag a 10 ton dragon out of the cage by the scruff of its neck and hurl it into a pit without any chance of it overpowering him and escaping.
Also there should be a chance to dodge the cage trap like any other attack particularly given that cages are such clumsy devices. It should be much easier to dodge a big falling cage than something like a flying crossbow bolt. Even with all of the nerfs suggested cage traps will still be considerably better defense options compared to the inferior path of actually bothering to make a military or using other types of traps but at least they will no longer be the laughably cheap and unstoppable God killing mega weapons that they currently are.