* This is an official 2017 NGUAC review *
My reviews come off pretty dry, so first off I want to say I liked Tropicool! Now on to specifcs...
Mixing, mastering and production: To sum up my thoughts on this account, everything basically sounds good. From here on it's just a point of improving all the little bits. I don't think I can offer better advice than to say just keep mixing and keep working at it - I think you have all the foundations in place, and over time you'll fine-tune them.
One bit I can say now is to make sure that all your instruments sound like how you want them to sound. What I mean by this is that in Tropicool you have a lot of basic sounds - piano, claps, hi-hats, kick, etc. - that sound like they're simply presets. This isn't necessarily a bad thing, could be a stylistic choice, but if you want your mix to shine it's really got to sound original, like you hand-crafted all the sounds. So carefully EQ and reverb all your instruments, as well as select the instrument sounds carefully.
Composition: The main thing that was lacking for me here was solid melodic content. You had some melodies, but to my ears they were largely instruments playing chords that happened to be at the forefront. If there were some distinct repeated sections were a great main melody was featured, I would have jammed so hard.
As I mentioned above a bit, having a lot of sounds that are very common lost you some points for originality.
Otherwise, one thing you could try is to surprise the listener. If I'm listening to a song and it goes in a different direction, or a brand new kind of section comes in, then I'll likely be pleasantly surprised. It also keeps things interesting.
Keep on composing!