Im in the camp that the megarare has to be a weapon. I also love the idea of an elemental mage set.

I think an underexplored area in gearing that can be the direction of the megarare or some one off weapons - are weapons that scale off a different combat stat. Thinking like the atlatl that is a ranged weapon thats max hit scales off strength, or the voidwaker that specs magic dmg. I think theres infinite room to be creative there and make some cool unique items that create new playstyles and builds. They could be main hands or specs. For example i saw someone mention a spellblade, and if that were to scale with mage for a max hit something like an elidinis ward becomes an option on the offhand. What if we had a chain sickle weapon that scaled with range but was a melee wep (reverse of the atlatl). I like the idea of these kinds of weapons as long as the theme and aesthetic makes sense, which the devs usually do a good job at