are there any logos or anything that looks like a manufacturer's ID in that instruction manual? a lot of times the same model is picked up by several manufacturers. clones of clones.
unlocking it and removing all/most the chinese software package would be the first thing i'd do, install the official store if you wish (which is tricky a lot of the time). or just install apps if you can transfer them to memory via USB and leave the store alone. preferably its got SD abilities
knowing what the chipset is would really help knowing what you could do with it. do the instructions have this info? maybe "rockchip" and some #s?
but, before you erase anything.... PLEASE go and listen/watch all the random media they include on them. i've found some totally weird stuff before, a lot of it is pop music though. one particular chinese girl group lately on chinese knock-offs, but i can't remember their name. girl generation maybe?