I was wondering if you had any tips on other ways to advance your career as a freelancer and demonstrate your progress too.
N.B. I mean ways other than just accumulating more projects in your portfolio.
If you want to level up, you will never get there being an independent development services provider. You are basically trading dollars for hours. Raise your rates all you like and you will still be up against that time ceiling.
Web development shops are hard to scale. It's an industry that's full of independent developers and small teams (unlike gaming for example, which is dominated by the big players and difficult to be in as an independent.) If you want to go big, then you probably need to switch the focus of your skills from providing development services to others to building your own products.
Don't accept less money for the next job than you accepted for the last one.
If you keep doing this, you will find that progress occurs naturally, or you reach a point where your earnings potential hits some kind of maximum.