I'll definitely make another scene, but it'll take awhile.
Oh and yes, I really want to add more character to the game but I can't think of anymore that would fit in with them. I do have something planned that will allow the game to have a lot more characters, but it won't be for awhile.
I am "technically" the only dev, but I do have a couple friends who help me out with some little things ( certain models, art, story, etc. ). Also I don't plan on hiring or recruiting other devs. This game is meant to be for fun, I don't want it to get too big.
I hope I answered all your questions, wish you well