Dynaman, Bioman, Changeman, Flashman, Ohranger -- Junji Yamaoka at his best. He always does such crazy, big action, he puts the performers through the wringer (regular performers AND the stunt guys), and he's also inventive in how the action LOOKS -- he can do frantic scenes with shaky cam and he can film personal fights with a cinematographer's eye, caring about the visuals, the location, the atmosphere. (As far as I'm concerned, Yamaoka pioneered toku's fondness for the whole "battle before sunset" thing that many tokusatsu have attempted to recreate.)
I mean, Yamaoka's great action is one of the only few things a show like Ohranger has going for it. Shows like Jiban and the Rescue Trilogy would be a hell of a lot less interesting without him, and they're more watchable because of Yamaoka's creativity and dedication to action scenes. A lot of Sentai action directors like Michihiro Takeda and even Kazuo Niibori imitate a lot of what Yamaoka brought to the franchise, but have never come close to matching him. Koichi Sakamoto with his shaky cam and super wire-fu is a joke compared to Yamaoka and his sensibilities.
Goseiger has a lot of Shojiro Nakazawa fights toward the end of the series.
You can't really credit Nakazawa, he's just a regular director who, while they can be present during fight scenes, usually leave action up to the action director and second unit for most of the show.
The regular director doesn't play much of a part. I mean...Ohranger and Megaranger had mostly the same director directors, but different action directors, and the difference is clear. Yamaoka's wild style is evident from the start of Ohranger -- even the opening credits have memorable action and Yamaoka's written all over them. Meanwhile, Megaranger has Michihiro Takeda as action director; Takeda's track record has always been spotty, but Megaranger doesn't have one memorable action scene. (Or even a good case of suit ACTING. Like, Takeda doesn't really do anything memorable with Hurricaneger, either, but there's at least good suit ACTING in that show.)