This is the crux of it for me. Don't get me wrong, I like me a shooter from time to time, but as I've gotten older I find myself not often liking the adrenaline

This is the crux of it for me. Don't get me wrong, I like me a shooter from time to time, but as I've gotten older I find myself not often liking the adrenaline-filled games being pitched. And Sim-type games really scratch that itch. They often have (relatively) deep gameplay mechanics that are easy to learn but hard to master, don't have a lot of time pressure (many are turn-based, or real-time but with no serious deadlines), and most importantly aren't multiplayer.