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.