Ron Gianti
SOC-11
EDIT:
Top, bottom, flank and rear armor will be at least half of the frontal protection listed. Halve the equivalent steel armor, then use the next lowest armor type. For instance, a TL9 light tank will be Combat Armor -2 across its front (12 cm steel); Battle dress across its flanks, top and bottom (6 cm, which is equivalent to Combat Armor).
Armored helicopters will be 2 armor levels lower on all facings. Unarmored helicopters will be treated as soft skinned. So, a TL9 armored helicopter will be equivalent to Combat Armor.
Most armored military vehicles will be armored as well as light tanks. Main battle tanks will be armored at least 5 tech levels higher. So a TL7 main battle tank will be Combat Armor -5 across the front; Combat Armor -2 on the flanks, top and bottom. Occasionally, a particularly cheap tank will have armor 1 TL lower (or *very* weak flank armor).
Didn't get a chance to really play this out, but I'm getting miniatures and hex maps and going to town in the next couple weeks.
Just from reading your armor factors though, it looks good and balanced. This would mean a TL15 heavy tank would have front armor of Battle Dress +13! An Auto Cannon at Medium Range (+6), firing Discarding Sabot rounds (+4 vs. standard Battle Dress), would hit on a 11 or 12 (not accounting for weapon skill). A PGMP-13 at Medium Range (+3) (+1 vs. standard Battle Dress), would not be able to hit at all (+4 -13 = -9!). Its side armor would be ½ 36 = 18 rounded to 16 (Battle Dress +3, +5) = +8. So that same PGMP-13 would need to get a side or rear shot and then would need a 12 exactly to hit (8 – 3 range, - 1 vs. standard Battle Dress, +8 = 12). Seems Reasonable and adds just enough tactics without being overly complicated.