I'm only 5'1 and quite heavy set. If I'm not carrying a big bag, I carry a very pouch or just my wallet. It's only just recently that I started carrying mid size bag. But I still feel this twinge that I ought to be carrying a bigger bag LOL
I carry an XL goyard tote. Inside I have a small clutch (LV pouchette usually) in case I'm doing something where I don't want to carry something so large & leave the tote in the car (run into the bank or grocery store).
I've always been a big bag girl, but carrying smaller bags as my everyday bags has caused me to downsize what I need as well. I love big bags, but when it gets to the point of oversized I tend to draw the line, and when I see girls toting around a bag that could easily fit a week's change of clothes in it, it makes me go .