Traps...... have been on my mind for a long time now.
Jerry rigged shotgun/tripwire traps please
Being able to place and possibly arm mines while stealthed would be awesome if not already possible (if I tried it I can't remember the result), and a drop in their weight would allow for infiltrators/stealthers to utilise them well, before a fight or rigging an escape route etc.
I like that traps have pretty reliable crowd control effects (bleeding, broken legs, knockdown), a few new traps with the same basic principles as the in game traps but with different effects would go a long way (disorienting or suppressing an area for example, setting on fire, poisoning, irradiating or bleed specific traps that force people to get treatment before advancing as another example, or even gas traps that K.O. people that can't make it out of the gas range etc).
It'd be awesome to see an extremely rare 1 hit kill trap, but I can see why one doesn't exist.
edit; traps are also already quite expensive and high tier in their crafting cost, so some cheap weaker traps could be quite cool too. I can understand you don't want people carpeting the city in mines if they get bored one day, so a placed trap limit could hinder such behavior a bit, maybe scaling with traps skill? I can't see why any one man would need more than 10-20 active mines at once.