That attack looked totally staged, if you look at the videos of the attack the gunmen were shot right at the entrance of the building. It must have been carried out by pakistan to garner some sympathy by claiming that they are also victims. If you observe the videos entire place looked vacant and there is only gunmen in the vicinity, it is as if place was cleared before for the shoot out.
There was nothing staged about Karachi stock exchange attack. I believe you are talking about Karachi Chinese consulate attack? Those fighters had no clue what they were doing and walking through the middle of the road spaying bullets like half drunk.
However, Karachi stock exchange attack was conducted by BLA and they claimed it through their official media outlets. Fighters were part of Majeed regiment of BLA
BLA fighters are not that good in urban areas anyways. They are deadly in their own mountain terrains of Balochistan, but not so much in an Urban fight.