Why are you developing a game that nobody will be able to launch/play? Sorry I'm really not trying to be rude, but this is what your comment implied. Im writing this because this game looks waaay too awesome for me to pass. I hope you can fix it soon.
First thing first is that all the games become not playable for some people due to technical reasons. You can not develop a game for all. Second is that Im one person who can not do much for optimalization if I dont know how to. And even to the future if the game gonna have bigger world and more NPC and more option it will be even more complicaited. So the only option is develop second game that will have worse graphics and loading screens when you walk somewhere. Its not easy. And I understand you but right now its not possible. If you dont like my decision you dont have to follow the game. I dont understand coding so developing it in...Unity wich is more for low games is not possible for me.