I don't know how you do this but you just keep getting better and better at a tremendous pace.
Your mixes just keep improving. If i have to mention one thing in this review it is the drums. They were pretty god damn awesome. I would change their sound a little bit (just to suit me) but overall they were amazing. I loved the shakers and all the little bits that just added up to make this song so 'engaging'
The only fault in them was the kind of hiss added at around 1:50 was maybe a little to treble-y. If the highs were scooped it would be little bit clearer and not as distracting (this is just speculation)
In my opinion the choir was pretty well done, maybe it lacked some low end in places but in general it sat well in the mix. The synth fit the theme of the song really well and the melody was quite stellar.
I think the song lacked some bass to make it sound more warm and full. I'm a sucker for plucky synths and noise effects and you used both in this song :3 To some people the song may seem repetetive but it wasn't a factor that made the song any worse in my opinion, it added to the, as you said "experimental" nature
In general this was a huge improvement over your past work. Good motherfucking job man!