londonmyst hit the nail on the head in her first para; i mean sums it up perfectly.
moreover OP you need to bear in mind it's one thing to write flawed (or 'offensive' as you call it) characters and quite another to write an offensive story. flawed characters are just an expression or example that exists in the world and sometimes they're even the hero of the story - and they are fiction; it's not like the reader takes it personally against them if the lead character is a sexist. however, if you write an offensive story that celebrates and promotes certain ideas then maybe your book won't sell that well. like is your story about a protagonist who's arresting homos and people of colour then sticks them in a gas chamber for societal cleansing and at the end of the book you all have a massive celebration like it was best idea ever and your hero has saved the day?
have you had any feedback from other writers, people you don't know personally? what did they think?
i can't help but wonder if you're putting your energy into the wrong worries. if you are self publishing you really need to focus and work damn hard at marketing and promoting your novel, especially if you've never done it before cuz there are heaps(!!! !) of self published novels on Amazon and it's easy to not get noticed. do you have a game plan?