The number of films Wakamatsu made during the 60s feels endless. Though his style is quite consistent, the quality of these films is a bit hit-and-miss, depending on their level of experimentation, political focus and no doubt the mood of the day. In '69 alone Wakamatsu made 13 films, so having an off-day probably wasn't even an option for him.
Compared to his other films, Naked Bullet is a rather straightforward genre flick. While you get your fair share of vintage Wakamatsu (i.e. rape, crime elements and alternating sequences shot in black and white vs color), the overall tone of the film is a lot lighter, mostly playing like a funky, sometimes even comedic gangster film.
It's a somewhat surprising departure from most other Wakamatsu films I've seen so far, but when you're making so many films each year it's really no surprise you eventually end up trying something different. Wakamatsu handles himself pretty well too, the film looks stylish, sports some memorable scenes and offers some good genre fun.