To your specific issue, my players tend to focus on offense.
My Armour Training lowered the penalty incrementally instead of all at once. It also increased AR -- I use a higher dice base, so it came in handy.The specialized Armor Training Talent might prove useful, although the PCs overcame an AR 10 Charnel Knight quite easily with a barrage of Mighty Blow and Lethal Blow stunts.
The one thing I'd say for both of my methods is that it allows for easy variation. Conscripts no focuses, trained soldiers the defensive focus, elite defensive and AR focuses. Players that build defensively might throw a wrench in that method.