1Gb EFI, rest of the disk LUKS with a single BTRFS inside. Use BTRFS subvols to divide things up. Swap as a swap file on BTRFS (be sure to set it as no_cow).
And / is tmpfs, /home is tmpfs, /nix, /etc/nixos, /var/log, /home/$username/downloads, /home/$username/documents, and some other directories are ZFS subvolumes bind-mounted at boot. That's only an option for NixOS or Guix though, so don't worry about opt-in state on other distros.
I prefer a very small EFI partition mounted at /boot/efi, that way the kernels and initrds sit at /boot alongside the rest ot the files (though if you also want encryption you need to add your encryption keys to initrd so you don't have to enter the password twice)