1. Launch's 100th jail break that hit the news in Age 779.
2. Pilaf's failed attempt to take over the world in Age 780.
Or stuff Akira Toriyama shared a few years afterwards in his interview about things that happened after the Majin Buu Saga with Mandō Kobayashi on March 24, 2013:
3. Yamcha's failed career as a club host.
4. Tien and Chiaotzu's farming career, and the latter's wealth.
5. Tien and Launch's romance, after she tracked him down.
6. Yamcha and Puar's life as freelance bodyguards who occasionally visit and help Tien and Chiaotzu with their farm.
Here are my suggestions based upon Toyotaro's own work in DBS:
7. Hatska explains to Irico the havoc that took place on Planet Yardrat when the Ginyu Force invaded it.
8. Shin's plea to the Grand Minister to revive Merus as a mortal.
9. Moro's telepathy which he used to communicate with Cranberry and Saganbo (behind the former's back) to plot the events of the Moro Arc.
10. Goku and Merus' training to obtain control over Ultra Instinct.
11. Monaka's first meeting with Beerus and Whis.
12. Jiya protecting the Galactic King on the Galactic Patrol HQ as the battle with Moro takes place.
13. The reason why Tien forbid Chiaotzu and Yamcha from taking part on Resurrection 'F' - they were sick with covid19, which temporarily lowered their battle powers severely.
14. Master Roshi's secret training during Dragon Ball Z which made him what he is on "Super".
15. Frieza and Shisami's 4 months training for RoF.
16. King Kai's celebrations with Bubbles and Gregory (giving him an official manga debut) that Goku no longer bugs them and destroys his planet with his training.
17. Elec's first learning of Granolah's existence back when he was a child.
18. The reason why Saganbo and his Galactic Bandits Brigade went to Zuno's Planet.
19. Yamcha, Tien and Chiaotzu's fight against Zauyogi's henchmen (seen above) after Zauyogi got temporarily injured by Tien's Kikoho.
20. How Yuzun faked his death and deserted the Frieza Force after Frieza took over.
21. How Doctor Gero kidnapped Lapis and Lazuli and converted them into Androids 17 and 18.
22. Mercenary Tao and Master Crane's ends, could be thanks to Super Buu's Human Extinction Attack.
23. How Sorbet took over the Frieza Force after Mecha-Frieza's and King Cold's ends on Earth.
24. How Berryblue and Kikono left the Frieza Force due to Sorbet's incompetence.
25. Bardock's relationship with Paragus, who looked down on him upon using his services in a conquest mission and viewed him as just another brute thug, much to the weaker Bardock's annoyance.
These are 2 page stories, it could be done with ease. All-in-all, there are 25 stories that could have been told to us in each of the almost-24 volumes to date. They already gave us 7 volumes with such "special/extra" additions.