Custom Card Reuse Existing Card

I want to create a custom card and potentially reuse / extend existing cards.

Bit of a generic question as I am still getting my head around Lovelace and custom cards so this is partly something I want to do and partly about learning.

I can easily create something like

using horizonal and vertical stacks and tiles which kind of does what I want but the first thing I want to so is turn this into a template type thing where I can add the card and define the room name, sensors, climate devices etc. I did hack around creating a custom card but it was completely bespoke which seemed a bit pointless in that these tiles do what I want just that I want to group them and make then dynamic (as the first step).

I however also would like to tweak the tiles with features to make them more compact and bring the control up into the white space next to the name, something like

but again creating this from scratch seems a silly idea

Anyone able to give me some pointers on where to start looking at building this up? (As I said, this is partly about learning and being able to tinker so whilst there are other custom cards out there that give similar results I am looking to do this in order to be able to create custom cards going forward and see how far I can take it)