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.
POWER OF DESIRE and "Let's Final Fusion!", the latter sung by both Masaaki Endoh and Hironobu Kageyama.
The aptly namedYuuki Aru Tatakai, practically the musical cue that the villains are about to get their sh*t wrecked in a truly epic way. Most of the series's best moments have this song accompanied them (the showdown with EI-01, the final battle with the Z-Master, GaoGaiGar vs Zonuda and Gai's EPIC beatdown of Palparepa)
Glass Cannon: The 11 Sol Masters from FINAL (with the exception of Pia Decem Pit). They're able to dish out a serious beating, but they have the defense of wet cardboard, breaking apart from even medium-strength attacks. Their "infinite regeneration" is the only thing that keeps them from being curb-stomped by GGG in combat.
Growing the Beard: The first 20 or so episodes are not actually that impressive and reveal the show as the kid's show it was... but around episode 27 or so, the quality of the story, the acting, the animation, the hot blood, and the absurdity all takes a sharp uptick and the show grows ever more entertaining from there.
In episode 3, the government decides to send a full assault squad and helicopter to "retrieve" little Mamoru, after the kid transformed and purified another monster. They have at least five guys yank the kid, thrashing and crying for his parents, off of his feet. All while saying that they didn't want to hurt him.
Also the previews for episode 31. A satellite drifting quietly in space, a close-up of a small rock beside it... spooky music? And then BOOM! FULL-SCREEN PASDER, complete with evil laugh and Pagliaccio DEVOURING HIM WHOLE. And just to top it all off? Episode 31's title: Farewell, GGG.
Episode 16: a university festival vanishes into a fireball, with little warning, leaving nothing but a massive crater. What would give small children nightmares is the way the attack is presented - it's very reminiscent of Sarah Connor's dream sequence in Terminator 2 and unlike any other so far, we see the injured and the scale of the disaster, implying that people actually died this time.
No mention of Guy's BRUTAL Beatdown of the Zounda? Sure, it seems awesome, but when you hear Guy's anguished and enraged shouts as he destroys the beast that contains Mikoto by ripping it apart, even after GaoGaiGar starts falling apart, you can't help but shiver. Watch and Listen... He doesn't even resort to using any of his attacks, just shouting in rage and tearing it limb from limb. And when it comes to the core... he just rips it out, no Hell and Heaven.
Padding: Especially prevalent in the first half of the series, the mediocre first half would have much shorter episodes if not for the constant blabbering during the battles.
Periphery Demographic: The TV series was originally aimed at kids, yet suffered poor TV ratings. Its popularity actually came from massive DVD sales to older otaku.
The rest of the Brave Series now have pages, but GaoGaiGar is still the most easily recognized of the eight. All but the hardest-core mecha fans will react with a blank stare and "Wait... there was a series?" when the Brave Series is brought up in the context of GGG.
Which makes it all the more unfortunate that it was canceled halfway through, just when it was about to get good. Apparently low sales sealed the dub's fate and season 2 was released subtitled only.
Toy Ship: Mamoru and Hana. Driven home with a big golden hammer at the end when their schoolfriends present Hana to Mamoru in a wedding dress, veil and all, before he leaves.
What Do You Mean, It's for Kids?: Yes, folks, this really is a merchandise-driven children's show at heart, and it's worth remembering that as you watch it. The original, anyway - FINAL was made for the Periphery Demographic that sprang up after the wee kiddies didn't really take to it.
The Woobie It's hard to not feel incredibly terrible for Mamoru after all that happens to him in FINAL.