just got back from seeing it and i really enjoyed it, couple of things
The whole O storyline kind of builds up like it's going to have a big impact on the ending, and it never does, that kind of bothered me. Also, i don't remember when K's wife died, was he married before his fling with O and she died before it, or does he have his fling and then he gets married/she dies? that kind of confused me too while watching it
The tie-in with his J's dad was really sweet, i remember (i think it was Griffin, or it could have been O) mentioned earlier in the film that J was their in Florida back in '69 so i did kind of see that coming at the end, but nevertheless i enjoyed it
K's wife didn't die. He disappeared after joining the M.I.B. and, at the end of the first movie when J neuralized him, he returned to his wife after revealing he'd been "in a coma" all those years. Then in the sequel she divorced him, which always kind of bummed me out. At least that's how I remember it.