PRESENT METHOD ( I didn't say the best)
I initially setup our template file(s) with the most inexperienced user in mind when we started using Acad Mech 2000 Power Pack.
As we use paper space layouts, I had a layout tab named A, B, & D for each of our paper sizes used , you guessed it, A, B, & D sizes! I saved a page setup in each layout named just like the above.
We actually could get by with one layout in the template file and choose page setups with the needed paper size, plot style, etc. defined within the page setup?
Is that the way you 'do' your template files?