Still, I don't think it's bad that you're getting bored after 40 hours. Just a friend of mine bought it and we are on a family account so all your recommendations and observations are perfect for me when I decide to install it and play it.
It's not always necessary to finish something 100%, you have to enjoy it and if in a few years you want to squeeze it to the maximum I think it's perfect, use that time to experience more games.