1) I accept that in the case of Fury I would let him die at all, but considering his important rol in the MCU and that there are still so much movies to be made, let's kill him later better... And about Loki, I'm not with you, that was a meticulous plan of him, and rocks ;)
2) About Malekith and Ronnan (more the second one) I accept what you say, but sometimes (as in real life) we have to accept that not everyone is so clever and smart, there are people like this, and if 'everyone' in the MCU were as you want, maybe that would be less believable...
3) It's true, Quicksilver can run faster than bullets, but in the movie he try to save Hawkeye and that child, so he didn't notice they were shooting at him. Also, I like you tell about X-Men: D.o.F.P., because MCU need to kill this character because the rights of this one belong to 20th century fox (X-Men and Fantastic 4).
4) I accept that maybe Iron Man II is your less favorite movie of all the MCU, but I don't think it's pointless and that they fight for no reason... If you have that ideology, the only fight with some reason are in: Captain America: The first Avenger (2 WW), Thor (ancient war with Jotunheim) and The Avengers (if not, the planet would get under the tirany of Loki)... Just enjoy every movie of the MCU as so many others, if you start thinking of the reason of ALL, you can't watch any movie (I accept you're right in some movies, but not this ones).
5) If you remember, at the end of The Incredible Hulk, Bruce starts trying to control the Hulk, but that does not mean that he has perfect control among him, maybe in some stress situation he can't control it and in some premeditated situation he can, if not... where's the point on that? Also, in the comics, he finally controlls the Hulk and finally act as one person.