What needs to be immediately Nerfed:
Decap Scrapper (throw mine and personal battering ram need 50% higher cooldown times), Static Shocker needs barrier bonus reduction to 40% of what it is now [even though this hurts core engineers too, it's got to go]
Holosmith: Reduce Grenade Barrage dmg by 10%, reduce Poison Grenade poison stacks to 1/grenade and reduce poison duration to 6 seconds, remove Lesser Grenade Barrage
Engineer General: (Remove Daze from Flash bang and replace with
Thieves: Shadow Arts needs to be addressed or if it cannot, reworked; the strength of the stealth synergy is way too high on daredevils. They have unmatched mobility, do a lot of damage (7 K backstabs from stealth and an unblockable daze via Swipe that has 0 cast time forcing other players to guess dodge), avoid getting hit because of so much stealth and 150 endurance bar, and cannot be crippled, immobilized, or chilled because of Unhindered Combatant Trait. Now I don't mind the damage and mobility synergy, given Thieves are in the lowest base health pool, but the stealth is just too much. Needs to go. The stealth mechanic in competitive is a problem anyway because if someone does that much damage, you SHOULD see it coming. Addressing Shadow Arts would also reduce the unbreakable chain of CCs that deadeyes can exert on a target - CC, immobilize, dmg, repeat until the target is dead.
For Condi thief specifically: Reduce the stacks of confusion that pistols can apply. A response to a condi thief shouldn't be the thing killing an opponent.
Tempests: Shock Aura should daze rather than stun, especially given Powerful Aura's AoE potential on 4 other allies, it shuts down another team's fighting potential entirely unless they have a guard. With daze, at least a team or player can run away.