Freeza's father was introduced very quickly when he came to Earth to help avenge his son's defeat on Namek. However, he was defeated quite easily by Trunks in his Super Saiyan form, without his transformations and true power being shown.
This character, if given the opportunity to display his true powers alongside his son Freeza, could have put up a great fight against Trunks and the other Z fighters, since Goku hadn't yet returned to the planet after his training on planet Yadrah.
[caption id="attachment_79007" align="aligncenter" width="1280"]
Image: Critical Hits[/caption]
7th Tien Shinhan
The strongest human in the anime emerged as one of Goku's main rivals in Dragon Ball when the Saiyan was still young, even winning the martial arts tournament in a final against Goku. In the Z phase, Tien continued his training to perfect his powers, even facing the Saiyan Nappa, members of the Ginyu Force (Freeza's elite troops), and Android Cell in his second form.
As the
series evolved, Tien Shinhan, although he continued to develop, fell far below the protagonists' power level, and although he has quite significant fighting power, he was left aside, becoming more of a spectator than an actual Z fighter.
[caption id="attachment_79008" align="aligncenter" width="1200"]
Image:
Nerd Hits[/caption]
6th Yamcha
Yamcha, alongside Goku, was one of the first characters to appear in Dragon Ball and always tried to keep up with the protagonist's evolution. However, in DBZ this gap became so huge that Yamcha ended up losing space in battles, and even the romantic relationship he had with Bulma from the beginning of Dragon Ball didn't continue after Vegeta's arrival, who took her from Yamcha, completely ending his relevance.
[caption id="attachment_79009" align="aligncenter" width="1280"]
Image: Ei Nerd[/caption]
5th Pikkon
Pikkon is a character from a filler saga before the Majin Buu phase. In this filler we see Goku participating in the Otherworld martial arts tournament and facing Pikkon in a disputed final fight.
After the tournament's end, Pikkon makes small appearances in the Saiyan saga, but considering his power level and the various techniques displayed, it would be very interesting to see this character have a more active role and even a Potara fusion with Piccolo, considering their power levels are equivalent.
[caption id="attachment_79011" align="aligncenter" width="1280"]
Image: Densetsu
Games[/caption]
4th Goten
Goku's second son was born after the end of the battle against Cell and although he had some prominence in the Majin Buu saga, his participation was limited to fusing with Trunks, without any deeper character development.
In the Dragon Ball Super series, expectations increased for better utilization of the character, but his evolution stalled, and although he has fighting power far superior to most other Z fighters for having reached the Super Saiyan level, he had no participation in any of the anime's sagas.
[caption id="attachment_79012" align="aligncenter" width="1280"]
Image: Critical Hits[/caption]
3rd Trunks
The eldest son of the Saiyan prince had an impactful appearance in the anime through a time travel intended to destroy the androids that ravaged the planet in his world, in a future where all Z fighters were killed.
His participation was crucial in the Android Saga, but after the Buu Saga, in which he served more as comic relief alongside (literally) Goten, the character was completely forgotten, even failing to participate in the Tournament of Power, the last arc adapted for anime in the Super series, despite having reached the Super Saiyan level.
[caption id="attachment_79013" align="aligncenter" width="1280"]
Image: Jovem Nerd[/caption]
2nd Piccolo
The Namekian was the main antagonist of the Dragon Ball series, but allied himself with Goku early in the Z series, and from then on developed his powers to very high levels, always rivaling in power levels with the other Saiyans, even without the benefit of countless transformations.
The peak of his development occurred in the Cell phase, in which he had great battles against Cell, Android 20, and the classic battle against Android 17, considered by some to be the most epic and balanced fight in the anime.
However, after the start of the Buu Saga, Piccolo seems to have been relegated to babysitting the young Saiyans Goten and Trunks, and even in Dragon Ball Super he was barely utilized, ceding space for the development of Goku and Vegeta. It's truly regrettable that a character with so much potential was left in the background by Akira Toriyama.
[caption id="attachment_79014" align="aligncenter" width="1280"]
Image: Legião dos Heróis[/caption]
Image: IGN 
