1. Hunchback Grid Iron: Having a 50% cooldown on a Gauss Rifle this mech offers a unique experience and the heavily extended range on medium pulse lasers are only seen on a Thunderbolt 5SS (if I'm not mistaken). Removing these quirks kinda takes away what this mech currently is.
Hunchbacks in general center around a single high mounted weapon which are heavily quirked.
2. Raven Huginn : very similar to the Grid Iron, 50% SRM4 CD offer a unique play style.
3. Dragon-1N : removing 50% AC/5 cd -> less dakka
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Now I actually do believe that these changes mostly affect currently strong mechs (Thunderbolt, Wolverine 6K, Grid Iron, ...) and they probably deserve nerfs but I think this needs to be solved differently.
Now you could in theory keep the play style while nerfing them by adding - damage % quirks based on the currently positive quirks, e.g. 50% AC/5 cd now would turn into :
50% AC/5 CD; -50% AC/5 Damage; (to counter higher ammo cost:) +50% more AC/5 Ammo
or turn the damage down to lets say 30% to accomodate for the much higher ammo cost. I'm not sure thats a good fix tough, but I really would like to keep those quirks so that the "identity" of the affected mechs will not change.