Before I continue with any of this, I just want to say this is great work and I critique as if I'm trying to develop a crop of professional composers with this jam.
As the Fog Clears
I love the chill sound. It's well mixed, and very relaxing.
I think it gets a little repetitive. I think this is one of the challenges of ambient music, is getting a structure in without making it too thematic, and simultaneously not making it too repetitive. I myself feel like I've developed a deeper appreciation for ambience this jam, because this was my big challenge.
I think for yours (and about many other entrants I've heard) is that I'd like more reverb to fill the space. We perceive large space with reverberation, and we perceive location with a few things, such as the time between the arrival of sound in one ear to the other, as well as the volume difference between ears. You can also imagine the physical impact that the obstruction of the head has, cutting off some of the highs.
One thing you can do is rub your fingers together with one hand on one side of your head, then plug that ear, and listen to how different the sound is in the other ear from an EQ perspective.
When the Spirits Come Out to Play
I like the opening, though I feel like it is maybe mixed a little bit murky/muddy. I think some of the stuff sounds a little bit like aimless improvisation (having done a loooot of aimless improvisation in my life lol). It still largely works and is cohesive, its just that some of it sounds a little thrown in there.
It still works and has a nice jazzy vibe.
Bioluminescence
I think my favorite so far, it feels the most balanced in the mix. The effect that it opens with I like quite a bit, especially because it is clean and balanced. Same with the little EP that comes in just a bit later. It fits in the space really well. The repetition of this progression I didn't find grating, but I think you could have paused and had a section with some contrast in this track so it isn't only an A section structure.
Great work, and I earnestly hope that my feedback helps, and I hope to see you next jam! :)