Well, first Hobbit was good fun. Second one got really rocky at times.
Anyways, I liked most of the Marvel movies so far...well, the first one in each series at least. Every two has sucked so far, except the X-Men "past" one. Both of those are actually my favorites so far. And Guardians of the Galaxies was so good I actually went out and bought the comics, though I've still yet to read them. I'm glad they're letting us know what's coming down the pipeline, although I'll probably forget what's coming out until a few months before their releases...
I feel like the second Hobbit was probably where Jackson + crew either thought they could get away with splitting the movie into 2 or realized that they needed far more time to really dive into the whole Battle of Five Armies thing the way that they would rather than treat it like a footnote (which is more or less exactly what it was to begin with) and further realized that there wasn't a good stopping point for a movie break since again, the Battle of the Five Armies was part of the story's Aesop and not that consequential to the main character Bilbo Baggins. Not helping matters is the elevated importance of both Thorin Oakshield and Legolas, the latter wasn't even involved in the previous versions (or maybe had a brief cameo, idk), and the former is basically the not-so-stealth protagonist now (practically hijacking it from Bilbo at times despite him being the one telling the story since its largely about his role in it, being one of the few survivors of the adventure and all).
Also, the X-Men: Days of Future Past one was done by 20th Century Fox and not by Marvel (since 19XXFox holds the license to make movies based upon Spiderman, Fantastic Four, X-Men and a couple of other things. This incidentally led to a conflict of character rights in regards to Quicksilver and The Scarlet Witch since both are X-Men (Magneto's children in fact) and official Avengers (which Marvel Studios holds the license for), which led to both series shoehorning in early cameos of their version of the characters (so now there's two actors and actresses playing Quicksilver and Scarlet Witch respectfully).
And honestly, sequelitis is a problem with Superhero movies in general since the first one is establishing the character and by the second you already know the score, plus the series best villain is usually used for the first movie which leaves the second either running with second stringers (or in the case of Batman; doubling down on villains since he has so many good ones).