I agree that there is no single 'correct' practice regime, but I think you underestimate the value of scales / harmony / theory in general. It is also a gradual process.

Whilst you can learn other people's songs (and that's cool too to keep you motivated), without some understanding of the underlying principles you'll struggle to make your own music, unless you 'understand it without understanding' as some people do - they recognise how things should sound, even though they couldn't explain why - nothing wrong with that.

As long as what you want to practice keeps pushing you, you're going to improve - whatever keeps you playing. It is important to focus on practicing things you struggle with, and human nature makes it easier to repeat things you find simple, which will not help you improve (much anyway).

Don't be down on theory though...