Currently, they're just sad, partly because the fact that there are only 4, and 1 of them gives you a 5% decrease in cooldown, while even 60sec cooldowns go to 57 sec, and that's just sad, so I propose speciallized harness'
Tank harness: Gives 10% increase in cooldown, but does 30% more damage
Speed harness: gives 10 % decrase in cooldown, but does 30% less damage
Big harness: increases range/radius of all attacks by 3 blocks but decreases attack damage by 7.5%
Small harness: decreases range/radius of all attacks by 2 blocks but increase attack damage by 7.5%.