Avengers: Infinity War Theory - Why Thor Is The Main Character
1. Containing (Or Destroying) The Gauntlet
There's already a suggestion that Thor and the Guardians find out (possibly from The Collector as he dies) that the Infinity Gauntlet was forged on Nidavellir (and that Thanos stopped the Dwarves forging anything else so it could only ever exist as a sole piece) and that's why they head there. That would make a lot of sense.
The Gauntlet is as powerful as The Stones, since it allows Thanos to harness their power: without it, the powers would be too volatile to actually use to his advantage. So it makes sense that the heroes would try to find out about the Gauntlet to see how best to take Thanos down.
The theory here is that Thor, Rocket and Groot are sent to Nidavellir to find a weakness in the Gauntlet or a means to stop it - heading to the source to discover an end-goal. That isn't to say, necessarily, that they light the forges to provide a Mount Doom to throw the Gauntlet's One Ring into though - it might be that Thor is told that the only way to contain the Stones is to forge something else like the Gauntlet.
It's definitely food for thought, anyway and it would certainly explain why that subplot is so elevated in importance in the film. What do you think?