I change out my bags often and tend to use the size that corresponds to my needs on the day, but I generally prefer medium to larger sizes. I have PMLE, so special sunscreen, sunglasses, gloves, and a parasol are a must for me in the sun - and masks and hand sanitizer are now probably permanent residents right next to my wallet and keys. And while I've managed to teach The Teen to carry his own sling bag, I still end up acting as The Husband's beast of burden more often than not.
But frankly, I don't mind carrying all the extras as long as I love the look of the bag.