Hi Derek,
My 53cm Aurora has worked well for my proportions - 5'8" with 32" inseam, and arms that are a bit longer than average. I have the handlebar set about level with the saddle. If the standover height of a 55cm frame suits you, my guess is that it may work better for you with your extra couple of inches in height over me. With hilly riding and touring in mind, I had the LBS swap out the stock crankset for a 48-36-24 at time of purchase. Try to test ride a 55cm and maybe even a 53cm and see which one you like better. I would recommend the Aurora as a good multipurpose bike choice. Cheers.