G'day Mike,
Regarding your templates for differing scales, the only suggestion I have is to draw everything full size, then using Print Preview just scale and locate your images to suit your paper size.
I used various CAD programmes as an Architect for many years, and used just the one template complete with all layers, blocks etc., which I opened with each new project, then immediately saved with a new name. I then worked on that.
When it came to printing I located and scaled to suit paper size, which in my case in those days was A1, A2, A3 or A4.
If you base your drawing around the 0,0 co-ordinate it can help with locating when using Print Preview.
Trying to give a full description is probably not necessary as there are good descriptions on using Print Preview.
Try these links for starters:-
http://wiki.librecad.org/index.php/LibreCAD_Brief_Overview#Printinghttps://www.youtube.com/watch?v=pvaHSfVJl78I hope this helps, I'm new to LibreCad and still feeling my way in so to speak, but it is an excellent programme, worth persevering with to adapt to your needs. I'm running 2.2.0 alpha on a laptop with Ubuntu MATE 16.04.
Hal.