@AnimeThighHigh How about learning Kyo-kotoba ( a ways of speaking in Kyoto). It will fit to a young girl, I guess. They speak slowly and it sounds sweet and graceful for Japanese people. For example “thank you” is “OOKINI”. The word is same in Osaka and Kyoto, the way of saying (intnation and pace) is different.
@AnimeThighHigh Hi, I think そか そうか そうですか are not difference meaning, but we distinct these use at situation. そか short of そうか mainly used teenager girls because girls think そか sounds more pretty. it's kind a slang way. そうか most common. chat with friends.we also say そうなのか. そうですか most common, slightly polite. if you talk with another person who is not close with you, add です / ます way will be safer.
I suppose ごぜいます is connecting with 落語（RAKUGO show). of course we don't feel any difficult, or perhaps sounds cutely. anyway, ありがとうございます is correct. please don't tens about it. I'm sorry bother you about long sentence. Than you.