One thing I am curious about going forward is whether we will find out anything about what happened on Knowhere, since gaining the reality stone was done completely off screen. I mean, yes, Thanos got the power stone by destroying Xandar off screen as well. But we basically know what we need to know in that situation. The reality stone is a bit different, as there were loose ends that I think at least some people are curious about.
For one thing, after the Collector's place basically blew up in Guardians I, we didn't even know if the Collector would still be there and if the stone was somehow lost/taken. I guess we can now assume that he rebuilt and that the stone stayed there until Thanos came.
The more important detail is whether Thanos took it by force, whether the Collector gave it to him, or something else. The Collector's comment in the end-credits scene after Thor:TDW was cryptic. It clearly showed that he was out to collect the stones. But for himself? For Thanos? For someone else?
Maybe none of that is relevant. But by the same token, it could be VERY relevant, especially if the Collector/Grandmaster theories floating around out there have anything to them.