Blood Music (story: 1983; novel: 1985), Queen of Angels (1990) and Moving Mars (1993) are my favorite Greg Bear novels, with QoA probably standing first, though it may not be the most accessible. I also had a collection or two of his which I replaced with The Collected Stories. Things like "Hardfought" (1982) may be better than any of his novels, or are at least in the same class.
His works cover a wide range, though the bulk of it and best of it is of the harder SF variety. Not all of that works for me, even when it's from the peak period, and he does seem to have lost a step after MM and had quite an apprentice period before the early 80s accomplishments, but his best is excellent.