For Eagle King thugs you really want to have an E9 bless, this is paramount. For equipment my standard setting is frostbrand, weightless kite shield, weightless scale mail and girdle of strenght. If I have a fire random EK I add brimstone boots.
Script them with blessing-stoneskin/ironskin (depending on opposition)-personal quickness-mistform-attack. They should be able to take out almost any amount of conventional troops with this setup. Indeed, a well made EK is more like a SC than thug imo.
The above example has prot around 25, def over 20, high damage, encumberance 3, quickness, lots of resistances etc. Try it, you will be pleased by its performance.