As the title indicates, I think it would be an interesting layer of complexity to builds to introduce components (of various tiers) to add to skill abilities, namely those that not only add values, yet also could change the way they function.
Moreover, I think adding another tier of components would be fun, namely legendary ones.
Component skill are kind of redundant right now (unless they lower or increase resistances). Greater Ice Spike, Greater Firelbast, Chaosbolts- they all loose their power in the end game. I rather have them as legit skills in trees, or at least having a new tier of components, suited for the Ultimate.
Greater Fireblast and Greater Icespike do scale well into ultimate, if you’re stacking the right buffs/debuffs and if you can spam them. Part of the reason probably has to do with the weapon damage component. With a good devotion proc they can make good primary attacks.
Greater Lightning Nova, not so much because of the energy cost.