Hi there!
I, too, think the Be Small would be too small unless you carry a purse as well. The Be Smart could work really well for you, but the Packabe and Be All are not HUGE bags. Once you add the clothes, two sizes of diapers, wipes, a toy, a few snacks, your wallet & keys then you might want to consider one of them. Do you live close to one of our retailers??? It would be great if you could see for yourself, but if not then go with your gut.
Good luck and tell us what you decide!!!
Joe