Thanos doesn't *need* to punish Loki. It was just a threat.
I'll say it again: Thanos manipulated
Loki. All he wanted was to get the Cube back to Asgard, so that Thanos can get into the vault and get his cherished glove back. He doesn't need to "punish" Loki, because it was all a ruse.
Odin, however, certainly has reason to punish Loki, and he'll probably either wind up in his mythological/Marvel place in chains with Jormungandr eternally dripping acid into his unblinking eyeballs (look it up if you don't believe me), or he'll wind up redeeming himself by saving Asgard from whoever invades it in Thor 2.
Yeah, I think Thanos will have a bit part in Thor 2. I think it'll come at the end of the movie, when Asgard lies in ruins after Surtur destroys it, and Odin lies dead, and Thor takes the throne. The movie ends, or post-creds, with Thanos finding the Gauntlet in the ruins, and putting it on.
That's where my bet for Thor 2 is going.