I recently went through and revised my thumbnails, they have been sitting at head height on my wall behind my computer screen. I read through them again and again and, coupled with some great advice about character development, I realised that I could push the thumbnails further. I have tried to include a few more shots that add to his relationship with the duck, he is dependant on the duck and he puts it before everything, in the original thumbnails I don't think that comes across as strong as it could.
In the beginning I have added a shot of him playing with the duck and throwing it up into the air, this will show him paying much more attention to the duck which I don't think he does enough of in the first set. I then changed the Spaceman's reaction to the the duck vanishing, I think all of this could be pushed and heightened a lot more, before I think he was to casual about the ducks disappearance, now he is much more distressed. Finally at the end like the ducks disappearance I tried to amplify their meeting again, so instead of just sitting down by him causally, Spaceman now flops down exhausted and grabs the duck pulling it into him, which I think is much more effective as essentially he has just lost his world and gained it back.