I love this idea! And you have must of what I'd want to put in there.
Man, I love Khemba.
You could probably afford to cut some creatures that like being equipped. It doesn't matter until you get the combo, and then you don't need to equip all of them. If it doesn't break the theme, you could just swap them out for some generically good cards.
Bearded Axe might be fun. Not until the combo gets going though.
Steelshaper's Gift would do fun things... once it stopped being a dead card.
Puresteel Paladin makes your lands cantrip and saves you on quite a lot on equip costs.
If you're confident you can get around it, and also a mean person: Stony Silence