I also noticed that some other character's roles changed, especially Gakupo's, but I kind of assume that's because each of these fics takes place in sort of their own universe.
I'm not sure how to take your emotion on "Uhn yeah", but I will say not to feel bad about it. What I saw was growth, and that's a good thing. It's okay to take some positivity to heart. Generally, I try to critique based on what I see established in a writer, so for you I see a fairly well-structured approach, so overall my takeaway after reading two of your works is that characterization changes from work to work, and that's fine as far as Vocaloids go. I just wonder how that would translate to a more solid state of character for higher level things like character development which generally aren't found in one-shots and rather in short stories or longer fics. If you'd like an example of a fanfiction author that does show some amazing characterization, I'd recommend ff.net user whutnot, although her most powerful works for me were the Claymore and Avatar: the Last Airbender/Legend of Korra works. She also has a Harry Potter one, and a few others that I'm not in the fandom of. Then again, if you don't care much for the fandoms her works are in, then that probably won't be of much help.