Which Linux Distribution Should I Choose for Maximum Customization?

Arch or Gentoo could be great choices for you considering how you want to customize your OS. Arch is a solid option for those who want an easier start, but if you prefer deep customization, Gentoo lets you compile everything as you like. I've enjoyed using Gentoo, but it does take more time to set up. If you're looking for something a bit less hardcore, you might also check out Manjaro, an Arch derivative, though I haven't tried it myself.

I use Arch because it offers a clean, minimalist setup. You get a bare-bones environment, and then you build up from there based on your specific needs. Gentoo is even more hands-on, allowing you to fine-tune every aspect of your OS. It really comes down to how much control you want—if you prefer working without a GUI, these options will give you the flexibility you're after.

Your Linux experience from WSL definitely gives you a good background. If you want flexibility and reproducibility, NixOS might be the way to go, although the learning curve is pretty steep. It's widely used in robotics for its portability. Just keep in mind that both Arch and NixOS are geared toward users who are okay with spending time tweaking their system.