NOTE: I only have access to/am using the website and the actual comic. If you find something either proving or disproving what I say from twitter, a livestream, or whatever else, please tell me in the comments. I read everything even if I don't respond. Also at this time, the newest comic is Episode 60 (pale horse) so anything that comes out after that isn't knows at the time of publication.
Lets first talk about afflictions
There are three mutants for Starsheet, one of which we have seen before as Delirium in Razor. I have the objects who will be next with the mutations
Red means they don't have starsheet, nothing to mutate; expect for razor, she has already a mutation.
Yellow means unlikely. Citrus already has his quirk, so not him. And I doubt to would be gum due to the object she's working with already having one.
This leaves Brandy, Spool and Comet. For Brandy I think he'll have something that makes him more violent and something that would be harmful for Sugercube. As for Spool, I think something that would make him stronger. Something that would make a threat to Citrus. Though I think his case is the least likely.
However the most likely(story wise) is Comet.We see that she has already started to hallucinate black worms and she is on her way to insanity so it wouldn't be surprising. Her mutation would be one of hallucinations (think Suitcase II) and insanity. This would make her hostile and dangerous to come apron but at the same time she would be fearful and quiet.
Next let's talk about Easter eggs. The rarer infections that happen with certain conditions
From the looks of it the Gestalt will be a building with spider like legs. Butttttttt the thing I'm wanting to look at is the Symbiote. We know nothing about her expect the fact that she's a female. This makes me think of multiple people but that one I'm thinking is the most likely is Maple Syrup
She has been mentioned a LOT in episode 53 (Remembrance). And it's clear that Brandy and Minty care about her a lot. And you know angsty this comic loves being.
Or I could be a new character entirely and I'm overthinking it.