As Paul said, it's all relative - I'm very similar to you - 5 10 1/2", 34 inseam, and years ago I would ride a 60cm frame. Fashions change, now I generally ride a 54cm, or a 56cm with a shorter stem - thats another variable. And I've not ridden for 8 months, so when I eventually get back on my bikes it'll feel strange. I don't think it's necessarily too big, but it depends on you, your riding style, and what you're doing with the bike. All you can really do is try it and see.