I think the TTK is just fine for this game. You just just need to play better and see to a possibility of acquiring better loot. I have had times when my teammates and I have had almost nothing (in terms of no favorable weapons, not a lot of ammo, no good armor, etc.) but have been able to take down enemy teams that have been beefed up. Is it challenging and a bit of a struggle, of course. But it's about how you play and strategise with your squad to take down such foes. It's why every legend has a unique ability, to be able to work with your team and sync an ambush or defenses and so on. Two three shots just does not fit this game at all, other wise, there'd be no need of helmets or body armor in the first place.