My .02 cents. I think it is better to over dress than take a chance... you can always take the tie and jacket off in the interview, if the "feel" is right (maybe could work in your favour to ask them if they are comfortable with the tie removal if you feel over dressed once there).
I would suggest going the conservative approach at first, by the sound of things ie even the question re earings on a guy, you feel that could be an issue... if that is your feel... don't do it. Get to know the company personally and make the judgement call after that.
Why give anyone an option or excuse to say "no", if you think something like that could be an issue.. take it out of the equation.