Remember too that hitting down gives the defender a bonus and you a penalty, so you will lose more units than hitting an even strength kingdom. And yes, if you are running wizards your KS is inflated which is giving you a false sense of your actual strength. Your army composition is all wrong - you have more caragous than pikemen and archers combined. You have no fodder to absorb damage for your ATC units. How many schools are you currently running? What's your wizard count?
And just looking at the troop numbers you mentioned, there's no way you were actually at 1.7 full GH. You had 418 land, 1.7 GH would be 710 GH total, and assuming no barracks at 50 troops each, you get about 35.5k units. Based on your losses in the BR plus the units returning, your total troops was 31.5k. Of those 31.5k troops, 18k of them were the 1/1 legions (of which most probably died in ranged phase). Not a shocking result to lose that battle when you actually look at the numbers.
