Itche and Feif – That’s interesting. I was raised very modern, similar to the way the OP describes. We kept what we kept and considered some stuff “extras” like covering your hair, wearing skirts and kol isha. We never asked poskim things, just the shul rabbi. I don’t think there was much holding any of us on. I never thought of leaving but I felt I had lots of freedom to do what I wanted, I never really learned any philosophy or purpose to any of it. For instance, I knew that if you wanted to eat on Shabbos, you had to make kiddush and hamotzie first. I didn’t know that you had to make kiddush and hamotzie for their own sake.
By the time I finished high school, most of my class wasn’t religious anymore. Some ended up “frumming out”. I am just surprised that the empty, buffet-style derech would be inviting to you. But you also seem to know TONS more than my peers did. I assume we are talking about two very different definitions of MO.
BTW, most of my family ended up becoming more religious to some extent or other.