I was gonna put TSL up there, but if you think about it, it wasn't really Obsidian's fault since LA rushed them for Christmas release :| And playing it with the TSLRCM really is great
ME3 was really really disappointing, because the other two were just so freaking epic to end like this was just really... ugh (though the rest of the game was awesome)
ME3 was originally promised to have 16 different endings depending on the choices of your Shepard character throughout the whole series, and we ended up with 3 endings with really only the color as the underlying difference. If Casey Hudson says that the writer's original dream for ME3 was good, he must have been smoking some serious stuff bro. The whole idea of Synthetics vs Organics has been cliche since the 70's, and I think they really wanted to copy of Battlestar Galactica, which is really hard to do. However, the extended cut did help out quite a bit to clarify stuff, but I really felt that the EMS was just utterly pointless.
P.S. - In the final battle, where the hell is the Geth, or even the armada of Krogan? Because I could have sworn I only see like 20 every time no matter the EMS...