Place-able traps, yes. Honestly there isn't a good reason why we couldn't buy/find and use those bear traps at least.
Hmm.
Enchanting:
Grand Soul Gem; Grand Soul
Lightning Enchant
Empty Grand Soul Gem
Grand soul gem lightning grenade or land mine?
Different traps would be good. Like ye said, the bear traps would be nice if you could use them.
Havoc mine.. watch them fly!
Monster spawn trap.. have some spiders you frackin bandits.
Clutter-it trap... Catapult type thing that throws random junk at the target. Bandits get pelted with cheese wheels and empty wine bottles.
Poison spike trap.