Purse help! What style?

I buy a new purse maybe every 3-4 years. I use it every day until it falls apart. I don’t match it to my outfit or the season. Fashion isn’t really an interest of mine, but I don’t want to be viewed as a frumpy old lady (I’m 34).

Usually I have a smaller cross body bag since I don’t carry much and like my hands free to deal with my kids. But it’s become a pain when I kneel down and it gets stuck under my butt trying to stand back up or it falls off my shoulder to the ground.

Part of me is thinking a more professional shoulder purse would be good. But I just don’t know! I’m a teacher in the Midwest, so I carry a backpack most of the year (also falling apart) and wear a winter coat more months than not. I’m also a hiker / camper so I co soldered something in that vein.

Help! What styles last the test of time better than others??