My suggestion for a fast style upgrade would be to embrace a pop of color or pattern. Try layering a bright, pullover knit on top of a dress shirt with a subtle or bold pattern.
I think dressing nowadays went from trying to fit in to wearing something to try to stick out.
I don't ever want to seem like I'm trying to command attention through the way I dress - but I have certainly been known to wear everything from a flamboyant suit to something very mellow and classic.