I mean we already have Waver and Reines as attack up 50% chargers. They aren't isolated chargers but so what. Isolated charges are limiting. Spreading out NP is better than not as it enables more possible comps. The only "advantage" to single charge skills like Skadi is if you're making the "takes less button presses" argument which, yeah, I guess you could make but that's not a gameplay consideration. It's more so quality of life.