Hi guys, I'm the author of that Gretchen's apocalypse fic. As for the Mami part, I admit that part could use sprucing up, and as for the parts with HomuMado, I plan to expand them when I write the final draft. Anyways, I'm thankful for everyone's criticisms so that I can correct them.
Now, I'd like to recommend a good KyouSaya fic that came out today
A Happy Dream. I feel that it's nicely written and I love Kyouko's character in it.