I've been playing through DE: Human Revolution the Director's Cut. First time I've actually sat down to see how it shapes up with the tweaks and all.
The Barret fight was definitely a nicely re-done thing, unfortunately the rest weren't that great. Nothing really noticeable with Federova's, and while the map for Namir's fight has been extended and gives you more options in the way of potential hacking or stealth, the frantic pace of his attacks tend to limit you from noticing it the first time around. At least until he's dead and then it's all "Oh, I could have used that."
I will say that if you run it with the Documentaries turned on, there are quite a few interesting tidbits on how and why things came to be in the game. Although there does seem a rather running theme of "we had this sketched out" or "half the map was done" or "this was planned for x.." only to have to be cut , dropped, or merged with something else due to time constraints. In fact a couple of the odd glitches in dialogue happened because the final passes for the writing team were done and then things got slightly altered on level design and things get shifted around, and not everything was tidied up and followed through on.
Although now I'm a wee bit frustrated, got to about 10 minutes from the end of the game and now I keep crashing out due to a memory error, then finding my save won't load so I have to re-load from about 20 minutes before.. only to have it crash around the same point. I shall have to ponder on this.