Nice! Okay.
I'm still leaning toward the thought that the primary upgrade targets for you are:
- A nicer amp ASAP That B30 is your limiter live. 100%
- More experimentation and learning with that behringer audio interface and Ableton to help your recorded sound.
- More playing experience with getting the tone you want from your hands (where you pluck the string at, dynamics, etc.)
In about a year with a bit more time under your belt, I'd be all over getting you to upgrade. I put a Seymour Duncan SPB-3 (high output! Rarrr rock n roll!) in my beginner Peavey bass about a year or two into playing, and that helped me cruise with my cheapie (cheaper and worse than your Mustang) starter bass until I saved up the scratch for a nicer instrument. So I dig where you're at and the things you're working on. Keep at it!
Here's
a jazz guy named Janek Gwizdala using your bass, completely stock with a new set of strings, getting some tasty sounds out of it (incl. effects pedals later in vid) That's a jazz context not a rock one, but I just wanted to show some of the things that great instrument can do!