you've missed the big ones..
teaching them an alternative to PC.xbox etc..
life lessons on accepting defeat and how to deal with it..accepting victory and how to deal with it.
time/project management..i.e getting models/project/list finished in a set time frame.
handwriting--clear and concise army lists
reading!!!-the rules/codex's require a lot of reading
take out the slaying the warlord/first blood, make it lighter
parents of the kids i teach after school..not so keen on the "whole death war side" so focus more on the skills