I responded to your message in case you missed it. Ill repeat it here again with more detail. Zone requires a decent amount of physicals to really work properly. In rookie, you don't have enough so they are generally slow to react. In my experience, it doesn't really shine until mid soph season. I generally run rookie m2m, then switch to zone in soph. However, the most commonly used zone play is 3-4 cover tiger and 4-4 OLB blitz. Just scout Lexington's defense in rookie, see what they ran. I believe they ran zone entire rookie.