HA Core requires you to install HA manually on an existing linux system, and since it does not use docker there are no add-ons, snapshots, or other features like that.
The version you installed has the same Home Assistant features as the other install methods, but requires the least knowledge on how to setup and configure a linux system to get it running.
Here is a summary of the different versions.
There’s nothing wrong or bad about your install method. It’s probably the easiest to get working too.
The only thing you don’t have access to are some parts of the base linux system, such as the integration in the original post of yours.
I’d keep with the system you have and just find other ways of getting the info like HDD Temp. For example this data is likely available via Glances which is available as an addon and available for you to one-click install from the add-on store since you’re not running HA Core (one-click to install, the configuration of it might take more effort, but as I recall it’s a GUI config integration now, so might be relatively easy).