These are what we call the 'YMMV items.' Things that some people find in this work. We call them 'your mileage might vary' because not everyone sees these things in the same way. This starts discussions in the trope lists, a thing we don't want. Please use the discussion page if you'd like to discuss any of these items.
Seven himself in the franchise, to the point where he has countless tributes and even sequels and remakes dedicated only to him. He's practically the poster child of the franchise along with the original Ultraman.
By extension, model-turned-actor Kohji Moritsugu. He and Susumu Kurobe are still associated with their respective characters and have appeared in various shows and movies, even reprising their roles. Moritsugu got to be captain of a kaijuu-fighting team three times (in Ultraman Leo, the movie Ultraman Zearth II, and the spoof Uchimura Sebun).
Eleking among kaijuus, according to an informal survey from Tsuburaya Productions. Second place: Windam.
Even Better Sequel: As good and as popular as its predecessor is, this show may even be much more popular, even compared to later shows.
Fair for Its Day: Anne went out in the field, flew the Ultra Hawk 3 (and one time, Ultra Hawk 1) by herself, and shot aliens often, more often than Fuji used to in her own show.
Uncanny Valley: The featureless aliens in "Seek Tomorrow" wear masks with blank eyes (think Batman in the comics) and unmovable mouths (like Michael Myers).
Vindicated by History: At the time, Ultraseven was considered a Contested Sequel due to its focus on the science-fiction elements rather than monster-stomping superhero action. Nowadays Ultraeven is consdered one of the all time classics, and is as iconic as the original series itself.
Visual Effects of Awesome: Seven's transformation, several kaijuu and mecha costumes (Guts, Eleking) and miniature scenery could have easily gone toe-to-toe with many of the feature-film releases at the time.