I’ve been daily driving Linux for 17 months now (currently on Linux Mint). I have got very comfortable with basic commands and many just works distros (such as Linux Mint, or Pop!_OS) with apt as the package manager. I’ve tried Debian as a distro to try to challenge myself, but have always ran into issues. On my PC, I could never get wifi to work, which made it difficult to install properly. I’ve used it on my daily driver laptop, but ran into some issues. I thought a more advanced distro, that is still stable, would be good overall. However, not getting new software for a long time sounds quite annoying.
I’m wanting to challenge myself to get much better with Linux, partitioning, CLI, CLI tools, understanding the components of my system, trying tiling window managers, etc. I’ve been considering installing Arch the traditional way, on my X220, as a way to force myself to improve. Is this a good way to learn more about Linux and a Linux system in general? I always hear good things about the Arch Wiki. Is there any other tips someone can give me, to sharpen my Linux skills? I was even considering trying out Gentoo on my X220, but the compiling times sound painful. I wouldn’t daily drive Gentoo or Arch, just yet, but I would try to use them as much as possible for general use.
I really do recommend doing a Gentoo install at some point, because I think you would learn a lot from it. It’s a really nice experience and a well put together distro. The compiling is potentially not as bad as you think, but there are a couple of packages that are notoriously painful to compile (there are prebuilt binaries available for some of the painful ones if desired too). You’d probably get a decent amount out of an Arch install too. Arch isn’t my cup of tea, but lots of people like it and it’d be quicker to get started than Gentoo. I’m not sure I’d recommend it for you at this stage but eventually you should check out NixOS too! You can even try the package manager out on any distro you want. NixOS is really interesting, but it does things a bit different from other distros, and if you’ve done an Arch / Gentoo install it’ll be interesting to see what NixOS does in contrast.
Other things to mess with… You mention partitioning, so make sure to check out LVM, and also consider reading a bit about filesystems. Maybe give btrfs a go :).
I wouldn’t worry about daily driving either Gentoo or Arch. Once you have them set up you’ll probably be fine.
Ironically the huge packages will have best security and speed benefits when compiled yourself