So Udina somehow contacted Cerberus to enact a plan that made no sense and could never work, even if Cerberus hadn’t stabbed him in the back, which he totally should have seen coming. Then Cerberus overcomes the Citadel defenses, gains control of the entire complex, and manages to do so in such a way that doesn’t leave any incriminating personnel or supply ships hovering around the place. You have a running battle then a car chase takes you to some other random location, and yet no matter where you go the place is filled with Cerberus mooks.
And then Kai Leng.
A good writer – like in Spec Ops – will make you feel like you were outsmarted, fooled, or out-maneuvered by your adversaries. A terrible writer will have his pet bad guy outsmart you by forcing you to be stupid. He’ll overpower you by taking away your powers and making you incompetent in a cutscene. The writers wanted to make Leng some sort of super-adversary, and their first plan was to bend the world and game mechanics to make him fit. Kai Leng has no personality, no world view, no history, no buildup, no connection to the setting, and no visible reason to oppose Shepard. What are the stakes for him? Why does he care? Why does he hate(?) Shepard so much? None of these things are established, because Kai Leng is an antagonist for the player, not for Shepard.
Yes, I know: “Indoctrinated”, the magical get-out-of-characterization-free card. Kai Leng is indoctrinated to some unspecified degree. Compare this to how Saren was portrayed. He was a complicated guy. I might pick at his plan, and not everything he did made perfect sense, but darned if we didn’t get a sense of who he was, what he wanted to accomplish, and why. Saren’s indoctrination was a tragic failing, a fall by a Turian who had more hubris than ability. Kail Leng’s indoctrination is a half-assed hand-wave offered to rebuff people like me who go around insisting characters need things like personality and motivation.
These are the things that BioWare fans love BioWare for: Characterization and world-building. Failing on these points is like a Mario game getting the platforming wrong.
The worst of all possible worlds is to combine BioWare style mechanics with Capcom style storytelling. At least in those games I’m not required to participate in the reason-destroying cutscenes. I can just go slack-jawed and wait for the stupidity to end so I can go back to the shooting.