A tux is too formal. A suit for an interview can't be too formal. Honestly, I gave up suits a few years ago but I would never dream of wearing jeans. Even though I don't have a full suit I have dress pants and sweaters. The most out of the ordinary I have done is bring a sort of hippie type bag. That was because the company was a hippie yoga type company. But my attire was still black dress pants and a nice shirt. And shiny clean shoes. I think the shoes are important. They are the thing you replace the least often and business shoes can be the most expensive part of your outfit. It shows you put care into looking professional.