Consider getting one made by someone who does serious sewing. My husband went to a craft fair (a professional one so these folks produce amazing stuff) and got me the best bag I've ever had: The interior is totally lined with pockets of varying sizes. Not just a pocket or two -- the sides and the ends too are all pockets, inside I can put everything (wallet, phone, keys, etc. etc.) into their own interior pockets. And the rest of the bag is very spacious. It is lightweight because it's strong quilted cotton fabric (but not cutesy-baby-quilty fabric, it's a classy tan/brown/olive earth tone pattern and does not scream "mom"). Empty, it weighs next to nothing. It has a zip closure so it's not hanging open all the time like some tote bags do. Best of all -- it's the only bag I've ever had that had a LIGHT colored interior. No more hunting for a dark leather wallet or my dark phone inside the black interior of a handbag! I can see everything inside at a glance because the interior is the same light tans and browns as the exterior! And it's all machine washable, which you cannot get with a leather bag that costs a ton more AND has a dark interior.
I would really get to a professional crafter and describe what you want. It may already be out there or you might get one made. But I've never before found any other bag that I could wash entirely, could see everything inside it, and that had enough pockets for items. Search online. I have no idea who made mine but there must be other crafters/quilters online who do the same kinds of things.
I think this bag cost about $65-$80 since I'd seen similar ones in the past at the same craft show. Leather bags by name makers would be the same or a lot more and you could not wash them, and I've never seen any other bag with all these interior pockets.....Yeah, my husband did fabulously well. I had not even hinted that I'd seen any such bags; he just saw it and said it seemed right!
And you could easily fit your larger camera and water bottles and snacks into this bag. I do!