Let me tell you a secret:
I overheard a young man in a piano lesson play a piece for the sixth week in a row. He clearly hasn’t spent much time on it beyond his lesson time; if he had, he’d be five pieces farther in the book right now.
Practice is the silver bullet. It’s where all your growth happens. Once you really get used to the speed you can move with only a small amount of daily practice, you will never want to go back to the grinding, slow pace of learning in lessons.
So, knowing this, your decision is obvious, if not easy: how good do I want to be? Does my desire for excellence merit five minutes a day? Ten? An hour?
Be honest with yourself. Only you can possibly know.
Well, that’s not quite true. We know, too, because we know when you haven’t practiced. And not practicing is the same as saying “I am happy where I am.”