Games that are in poor taste (e.g. racist, sexist, contain hate speech, etc.) will be removed from the jam, but I don't control whether something gets removed from itchio. Note that I've never had to remove a game for poor taste and I don't think you'll need to worry about this.
Regarding your second question, see the bottom of the FAQ for some tips! It's also up to you to be creative in how you'll design a game where the experience is surprising and unexpected - that's part of the challenge and fun :)