First I want to say that what you added is good. However usually when you compose music you want each instrument to be consistent in some way. Every element added to this song transitions in 25 seconds in AT THE SAME TIME, then drop 9 seconds later AT THE SAME TIME, never to be heard again for leftover minute and 15 seconds. It's rough and inconsistent, which I think is a big problem. Again, great idea, and the additions sound nice when they're together, while they lasted, but the way they cut in and cut out disfigures the song in general.
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