This smacks of placing limitations on one’s holiness. God does not place an imaginary line that rates how holy we are on us. Rather holiness is a more all-encompassing term. Asking this question suggests that one would like to sin “just enough” to know how bad they could be without spilling into hell.
An adult sense of faith places us into a new sense of relationship with God. This relationship requires participation on our part where we place ourselves in our human weakness before God and humble ourselves in that presence. It’s not about how holy we can be, it’s about always trying to be as holy as we can be.