I think Gentoo is mostly a meme, but Funtoo is a modified version of Gentoo made by Gentoo's creator which simplifies things like USE flags that Gentoo uses, for example a tool in Funtoo called epro is used to manage USE flags in batch, while using arguments to tailor the USE flags (in batch) to your system; In Gentoo you would have to fill up a file called /etc/make.conf with a bunch of USE flags, which you would have to research each and every one of; But in Funtoo epro is really handy and basically does the work of setting USE flags for you. I think Funtoo is an improvement over Gentoo tbh, but I don't use either.
To this day I haven't been able to install Gentoo or Funtoo since on Funtoo Nvidia drivers must be messed up or smthin because the system just hangs at boot, and Gentoo took too much time to install and the install guide wasn't concise enough/ I was too lazy to install it that day (compilation of everything is quite annoying even though it may "improve" the packages speed through USE flags, it just took too much time for me tbh). I might try and install Funtoo again some day, it's just the fact that it takes a lot of time to install (depends on how fast your system can compile things, on my system compiling the default Funtoo kernel would take like 8 hours, and I don't want to wait that long just to install an OS).
Right now I use Arch linux (it's way faster to install than both Gentoo and Funtoo) and the AUR is really nice, I use the window manager XMonad which is what I prefer, but everyone likes different window managers (it just depends on what you want I guess). I try to configure XMonad in a way in which it doesn't get bloated with keybinds (since I can't remember all of them).
I think you should try Arch before you try Gentoo or Funtoo, since Arch gives a decent "introduction" into a barebones setup with a few hundred packages (I think?) installed by default, and it is a binary-based distro (rather than Gentoo and it's modified versions being source-based distros, this means you have to compile packages basically), you can build up the system like what Gentoo/Funtoo let's you do (Arch doesn't come with the USE flags thing though).
I am glad to see a fellow tiling WM user, they really do improve productivity tbh.