I have a separate boot partition so the rest can be encrypted with luks. That’s all that’s needed in a large majority of scenarios. Most other setups end up needing to resize something at some point which in many cases is a total pain.

On my primary PC I do have a second hard drive for documents and other long term storage files that I want to access more often than on the NAS. This way it’s nearly impossible to lose those files of I reinstall something and it can act as a temporary backup storage for settings files when I do reinstall stuff rather than having a partition that wastes space or runs out of space.