Originally Posted by Torrilin

Geometry does matter sometimes... but the bits most people worry over aren't the bits I have found actually matter. Effective top tube matters, tho given the OP's preferred riding position, not much. If he wants to try drops, it matters a lot more. The bottom bracket height matters a lot. It dictates chainstay length to a remarkable degree (especially if you're short), and affects all kinds of stuff with stopping, general handling and the bike's ability to handle heavy cargo. I wouldn't say there's a hard and fast point where the bottom bracket should be tho. Some of the guys here on BF can manage 40-50lb loads with much twitchier bikes than I can, because they're taller and heavier and just plain have more weight to shift around.