As I think about it... I think I want Senko to have modes herself enough to start learning basic techniques by the end of the Chunin exam. The end of the exam is apparently always a tournament and I kind of like the idea of her ace in the hole actually being something incredibly basic.
Probably at least one mod should be something she gets during the exam.
Edit: Bit of Trivia: In Naruto Dragon Blade Chronicles, the non-canonical videogame with the Western Style Dragons and the somewhat nonsensical plot, it is established that, should someone combine the power of the Five "Genryu" ("Being dragons," basically an incarnation of one of the Five Elements) within themselves or else merge them together it creates a "Light Genryu" that can use all five elements plus "Light" which is treated as something special and amounts to laser beams.
In the game it's treated as "Nonelemental" but... Yang Release is translated as "Light" by the anime dub and it does, after the fact, make sense that the Genryu would be Yang aligned beings(they're treated more as mindless animals than spirits or thinking beings and as long as they're all in balance and not pissed off they have a nurturing life-giving effect on the land around them.)
This, combined with the fact that Viz translates Yin Release a Shadow Style and we know for a fact that Yin can manipulate shadows in canon(Shikamaru's techniques are all Yin Release) and I'm wondering if "light" can't be an application of Yang Release. (Bonus: While depicted as Red in the Anime, in the Manga Physical energy, and thus Yang Release, are depicted as white while Yin is black.)
Becuase otherwise all we have to go on for what Yang Release does is Chouji's body morphing techniques, Kurama's yang chakra bringing dead wood to life, and that healing techniques can be yang release while we have a lot to go for with Yin.