(and no, Deux Ex 2 never happened).
It wasn't as terrible as Star Control III's blatant disregard for all things canon, for instance, it just wasn't of the same caliber as the first game. People say the Elite Force (Star Trek, not dystopian)
games were really good. I'd rate it about as good as one of those. Maybe better. Those don't have any kind of augmentation or give you the option of stealth or character customization.
The only real issue - if you patch the game - would be the bugged multitools that don't stack with your regular ones, crash your game later on if you put one in your inventory, and start replicating if you fail to pick one up. To which you keep your inventory full at all times, ignore them if they fail to stack, and pay no attention to their replication because leaving them on the ground won't crash your game, and they're NOT safe to take.
That and horrible slowness on any graphics cards that existed when it came out. Or slightly after it came out. Modern ones should have less trouble. Okay, so it is really badly optimized. (Hazeron somehow manages to run much worse while also looking like something from 1994, don't even ask me how)
(Of course some augs and weapons are just better - the emp drone aug is the best way to take down the power armored templars, not even the mag rail compares, and trying to shoot the weak spot on their armor, whereever it is, is just a waste of time when you can send EMP drones at them from out of visual range until they fall down and explode. It's not like there's any shortage of batteries or whatever you use in the game.)