From what I learned from interviews and comments about the director of this film, Taika Watiti, a lot of the humor seems to come from his style more than any editorial fiat (Though maybe it was mutual both for him and the people in charge?). I also did hear he wanted to take Thor in a different direction, taking influence from some eighties films and the comics. Apparently more than half of the movie was ad-libbed, with presumably the script acting as more of a rough map than anything.

I'm sad Jane and company aren't around, though the most I can picture of their role during the gladiator planet sequence is them being kind of bumbling around trying to figure out to help, being mistaken for tourists, and taking selfies with some of the aliens or warriors are either confused, annoyed, or really come into it (i think Darcy might initiate that last action?). It's sad Sif also isn't there but apparently that's because the actress couldn't make it because of scheduling conflicts. I heard some word of god that says that she was exiled out of Asgard, so at least there's hope she still lives.

Still, the trailers for this movie did peak my interest and were fun, though I can understand why it might turn some people off from what I hear. Still, I look forward to seeing it when it comes out in the States.