i kind of like it when directors don't simply spoon-feed plot to the audience but leave some questions unanswered and some lines to be filled in by the audience themselves.
Sometimes that works. Sometimes it doesn't. IMO in Sunshine it didn't work. But we can simply agree to disagree. IMO I think what Danny Boyle was trying to go for was to break the trend of reality and delve into surrealism much like he did in Trainspotting in the toilet diving scene. It worked for Trainspotting it didn't really translate that well in Sunshine a movie that tried the best it could to be grounded in science even though it got the whole artificial gravity thing wrong lol. If you ask me Danny Boyle should have gone the extra mile and gotten a rotating set for the interior space ship shots like Stanley Kubrick did in 2001: A Space Odyssey.