This is a beautiful composition with some lovely chromatic harmonies throughout. If you showed me this piece out of context, I don’t think I would have guessed it was supposed to be based on the theme “3, 2, 1, blast off”, but there are pieces of it that I do think work well with the theme. For example, the first three chords do sound like a countdown from 3 as they move through different keys rapidly. The second lighter part in 3/4 has the most memorable melody and I think is very well-composed. I like that you reprised the intro at the end to round it out. Overall quite impressive, thank you for sharing!