Sweet this is quality feedback. First let's start with the save file location, if you rebound your keys you won't be able to access the doll system right now. We are working on a hotfix but the location of the save game is here
C:\Users\username\AppData\Local\SapphireSafari
Just delete that guy and you'll be able to use the default settings without issue.
"Volume slider for music doesn't do anything. May be my circumstance, not sure if others have the same issue."
We will fix this one.
"The gallery needs a system by which you can select and delete photos en masse"
This is coming in a future patch for sure. We will have it tied to progression and deal with "saving photos" in a different manner, aka the temp photos are deleted after each session unless you save them.
"What I hope to see in the final product is quests, a basic story, a way to give the photos value (like trading for currency which you can by props, toys, interactables), and perhaps a system of upgrades for your equipment, it would also be nice to have a camera stand and remote triggering for the camera."
The game will have a main narrative to follow, along with side objectives and a pokedex to fill out. Camera will have hidden upgrades in the map, including lenses, fire modes, storage, filters, etc. There is also player tools, throwable bait, etc. Dunno about the camera stand, but we might do something with that idea, maybe.