Be creative here there are no wrong ideas.
I would like the Spartan laser to be a weapon personally, just called something different "Charge Rifle" was a name I had in mind
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Melee weapons with elemental damage. Two handed variety (great sword,battle axe,maul etc.) Maybe smaller dual wield ones. Shield similar to phalanx one. Be awesome if they gave melee weapons its own slot and make them upgradable with their own perks.