This was beautiful! I know I'm very (very) late in the game, but I just had to let you know how much I appreciated this story in case you still check your messages!
In the game, I found Gamma's story very tragic, and it was made even more so by the fact that no one but him, his now-dead brothers, and maybe Dr Eggman really understood the sacrifice he made to save them from a torturous existence.
Also the fact that Amy probably had no idea what happened to him.
But here, she does understand, and sends him on his way with some kind words! I like Amy as a character, but I feel like her relationship with other characters is often glossed over in favor of showing how cool she thinks Sonic is. This translates to fanfiction, too.
But here Sonic shared space in her head with other characters, too, and that's one of the few fics I've read where her whole character isn't defined by Sonic (but then I tend not to seek out fics about Amy)
I also liked the descriptions you gave of the setting, and it made me feel like I was really there in the character's head. (Such as Amy being grateful for her gloves acting as a barrier between her hands and those pesky bugs!)
As for the procrastination part of it. . . I can completely relate! I'm currently working on a Medieval Sonic AU loosely inspired by Arthurian legend and the Once and Future King, and I'm always finding some new reading material to procrastinate with! Still, I think the research shows in your final writing, and I like how you connected this to Tails' story in SA.
Thanks for this awesome work! It shall go down in history!