It’s not too much if you can handle the weight and still enjoy yourself. I would certainly err on the side of more water if sources will be infrequent at times. You don’t always have to fill all your capacity if sources will be frequent along some stretches. Consider light versions of things. E.g., synthetic, convertible pants instead of jeans. Take the DSLR if you intend to make good use of it. I crossed the US and then some during one trip with an obscene amount of film camera equipment because that is what I wanted to do. Never regretted it even though many days would have been easier without it.