This movie doesn't work, I'm afraid.
Now, I could critique any number of plot points (like why Blofeld's henchman is still trying to kill Bond even though he's just heading right to Blofeld's residence, which is apparently where Blofeld wants him; or why M needed Bond to kill that guy and what exactly she knew about this whole situation), but the truth is, most movie plots, particularly in spy thrillers, can be picked apart. People said, correctly, that if you think much about it, the villain's actions in Skyfall (or The Dark Knight, from which the former borrows heavily) are absurd. But the reason that I thought Skyfall was a great Bond movie and this isn't is all in the character. To me, the improbability of the villain's plan isn't a big deal, so long as the character dynamics compel, which in that movie they did; Silva was a strong villain, and the movie worked, because I bought his vendetta against M, and the way that this affected M and Bond. Here they bring back Blofeld in a way that feels like the first draft of a script meant to create a closer link between Bond and Blofeld -- but like I said, it's a first draft, because there's just no there there. It doesn't add anything noteworthy to Blofeld's character, or Bond's, and nor does the attempt to make this feel like the culmination of the previous Craig movies feel natural.
I quite like Waltz as Blofeld, for the record. There are a few moments that he sells really well. But there's just not much to the character, and even though the movie leaves him alive, I can't think of any pressing reason I'd want to see this character again, which is kind of failure.
I'm a big fan of Lea Seydoux, and she has some very good moments here (and, of course, looks amazing), but there's some very ropey plotting around this character, like her suddenly running off just before the climax (for a character reason that really has not been built up at all), solely so that she can be captured and used as a hostage in the final minutes. More generally, I'm not how this character fits into the franchise. Most Bond movies end with him heading off for some R&R with the main romantic interest, of course, but this movie drops the "love" bomb and his choosing to run off with her instead of killing Blofeld (another dilemma that really doesn't fly; Bond isn't the Punisher, and if we're meant to think he's being driven to the edge by this guy, I really didn't feel it) is played like some sort of turning point for the character. I don't object to that in principle, mind you, but is that really going to be followed up on?