Spring trap upgrade..make it useful or make the price match the uselessness
Make level 5 springs bounce off 20 troop space because single troop differences are pretty worthless. Being able to rid one more giant or hog would make the upgrade scale almost seem worth it. Another way to help it seem worthwhile is to make the traps release faster with upgrades. Make it less likely that a fast troop like a valk can run over it without being effected. Right now the cost vs effect is pretty lopsided and needs adjustment.