Hello, my name is Robyn and I compose chiptunes and MIDI music, both for myself and for game projects. My primary focus for chiptunes is the Amiga, making authentic MOD music in OpenMPT and Protracker. I also use trackers such as 0cc Famitracker and Deflemask to compose songs for other systems.
Hope to see you all around ^-^

Agreed with this comment, though the lead also sounds like it's phasing. Is it 2 square waves playing the same note? I suggest adding vibrato to just one of them, and itll sound really cool and still layered!
I have to say, I don't think any improvements need to be made to the composition. It sounds really nice as is.