Not bad at all! Still room for improvement though.
First of all spend more time working on your melodies, they still sound a bit confused and random (like someone just improvising on a keyboard). Try listening to other stuff for reference or watch some music theory on melody building. Also the flutey sound at 0:48 really cuts through you like nails on a chalk board, needs EQ and levelling.
Id try to experiment with different basslines and add more variation because having the same bassline or very similar ones throughout make the song get boring eventually. For example with the bass at the start have a variation that goes up in pitch before returning to the root note again as well. I don't really have any problems with the mix, it sounds solid to me.
One thing you could give me a few lessons on is making breaks, you are an absolute wizard there.
Second collab attempt fell apart as well... thinking about attempting a third at some point if you are cool with it.