I have someone I see on a daily basis that is very religious/christian. I once asked her about how God can be all knowing and at the same time grant me free will. The two cannot co-exist. After a few minutes she said, God's just so big". This is her, and other christians I know, response when they cannot answer a question logically. His plan is just so big. Your childhood questions are good ones but I can tell you now, that is where they lead he's just so big. I enjoyed reading your thoughts on why young people are leaving, I think it's pretty spot on. I know a number of young people that think of Christ's teachings as more of a philosophy. I tend to agree with this.
I followed Taoist philosophy for a while - and it worked very well for me, kept me in balance - until I found out there is a Taoist religion, complete with its own rituals, pilgrimages, recitations and such. That took the wind out of my sails. It gave me the distinct sense that most people are followers, not thinkers; that they prefer to be spoon-fed dogma that agrees with what they already believe rather than to think critically for themselves; and that they prefer habit and comfort over truth. It is a realization that haunts me to this day, like a war wound that heals over but nags at you the rest of your life.