well, they could have balanced it more.... i mean, they left in that ridiculous grenade wall tag
Not about that. 2 piecing was an art, and it was enjoyable. They could have continued with it in a form where it wasn't overpowered with server connections (2 piecing was never a certainty on P2P) and made it another form of a dual.
Art what? You are certainly in the extreme minority if you think two piecing was enjoyable.
The very fact that you got stun locked and couldn't even move is why two piecing was a problem in Gears 1. It was always a certainty in Gears 1, even with lag. I used to play Gears 1 from India with 250-300ms of latency (almost always 1 bar connections) and the only reason why I was still able to get kills outside of the random hits was two piecing which worked every single time, it was the only way for me to play a game because how ridiculously easy it was to get kills in that manner than doing anything else despite the high latency. Infact, you had to be quite terrible to miss two piecing in Gears 1 despite the lag.
You can still melee and shotgun someone, you've always been able to even in Gears 2, Gears 3 and Judgement. The only difference is that your enemy doesn't gets stun locked for you to land a free shot. You wanna use your art go ahead, but you don't get a free shot just because you landed a melee hit. If it really was suppose to work that way then melee would have been a one hit kill.