Well it seems more and more burst-generation type himes are coming out recently as well. I've been noticing a lot of himes introduced in the current generation with burst gen type abilities, so I agree with you that you could probably branch Shingen to other elements. I'm sure it'll be possible to set up Shingen-builds for a lot of the elements when her wpns come out in the future, as long as you had all those right himes.