Qui-Gon Jedi Spirit Training: Can not happen. For the simple reason that at the end of Jedi, Anakin's spirit shows up with Obi and Yoda. Vader certainly didn't get this special training from the Q man, therefore it contradicts the films.
Padme Dies of a broken Heart: Just lame. I would have bought complications in child birth, internal bleeding, trauma from the force chocking, hell, even smoke inhilation, but lossing the will to live when she now has 2 children? total bull.
Padme dies during childbirth: A repeat? Nope, a continuity error now. Padme can't die during childbirth. Liea tells Luke that her real mother died when she was very young, and she can only really remember images and feelings. to be really generous, Padme could die, at the earliest, when Luke and Leia were roughly2, but more likely 3. And don't use the force as an excuse, that's just weak.
Obi-Wan is there for the birth: Another continuity error. Obi-Wan doesn't know about Leia, only Luke. In Empire he is unaware of Leia until Yoda tells him "there is another". Some will argue that this is open to interpretation, and so it is, but I maintain that Obi-wan seems to be pretty clearly in the dark about Leia's existence until that point and gets filled in by Yoda after the fact. It also makes more sense. If anyone ever found Luke or Obi-Wan, he wouldn't be in the position to give up the existence nor the location of Princess Leia.
Vehicle Design: The ships are cool, they really are. The problem I have is they all look like they come after the vehicles of the original trilogy, not before. I personally would have had the army of the republic using x-wings and nebulon B frigates and such, all looking brand new and well painted. That way, 20 years later the rebels look like they're using old discarded ships, and the Empire looks like it merely got a new military contractor.
Anakin's Turn: Anakin is clearly the stupidest Jedi in the history of the Galaxy. Palpatine reveals that he is a sith lord and Anakin doesn't start piecing it together? "Hey! that means you started the war! You're responsible for Qui-Gon's death! You created the clone army! You tried to have my wife assasinated! You had me sentenced to death! You control the seperatists! You had me kill your own apprentice! you've been trying to turn me against the jedi!" But no, none of this apparently goes through his head, and then when he arrives to find Mace and Palpatine facing off, Palpy lies to his face "I'm too weak!" but as soon as Anakin intervenes, suddenly Palpy is back at full power and blasts Mace out the window? Hey kid, he just lied to your face! not to mention he tried to make you think Mace was trying to overthrow the republic AFTER you walked over 2 jedi corpses. You think Mace did that maybe? You know, if Lucas had just characterized Anakin as a dumb jock, none of this would matter. If the audience just believed Anakin was stupid, we'd be in a better place
Buzz Droids: Okay, neat idea, clearly a destructive and devestating weapon. So why are they no longer in use come the original trilogy?
R2 the Acrobat: Atroo can fly? Wow, that sure woulda been useful in the OT.
R2 keeps his memory: Lame. Just lame.
Vader the thespian: "NOOOOOOOOOOO" Worst. Line. Ever.
Wookies: Their inclusion was entirely pointless. And Chewbacca being there? Wow, what an incredible coincedence. What a small universe. What a bad idea.
General Grievous: Wow, you know you're doing something wrong when the cartoon version of a character is more interesting, threatening and compelling than his feature film counter-part.
Okay, that's enough for now.