There's a few things I can think of that have been left open-ended:
—Universe 10's Gowasu put Goku Black/Zamasu's time ring in a box
All the time rings in that box are green
except for one which is grey. That's how that arc ended... and I think that could be
revisited later on.
—Future Trunks and Future Mai are sent into a different Future
where another Trunks and Mai already exist. How is that universe
doing with 2 versions of them? How are the future Gods feeling about it?
—The latest character that was unveiled on Super's website is an
Universe 11 Warrior (Toppo) who is described as being so powerful that he's
being recruited as the next God of Destruction of his universe (to replace The Clown whose name is Vermouth)
Which means that it could happen in U7 too... Beerus having to resign and
give the title to either Goku or Vegeta. Or maybe later down the line (after a timeskip)
Goku trains Uub and presents him to Beerus to make him the new god of destruction
—Maybe the Dragon of the Super Dragonballs gets into beef with Shenron and Porunga (Namek Dragon)
—Cabba told Vegeta that there's somebody on Planet Salad in U6
that reminds him of Vegeta. Vegeta said that he'd like to meet him
one day.
—Since Zamasu was an enemy from Universe 10, it's
totally possible that foes from other universes could cause
problems... Or Kais get corrupt, and start fusioning and stuff like that
—Having a Future Zeno and a Present Zeno could end up being
problematic, and maybe entice something where everybody gets lost
into different timelines (Remember Chrono Trigger? Which Akira Toriyama
was involved in. When Lavos goes ham in the Ancient Civilization's time,
he blows mad people away into different times. Magus was sent to the dark ages,
the old man was sent to the end of time, etc)
—Maybe Goku becomes a lunatic as he gets older
to the point where Beerus has to kill him
By the way,
I've noticed that this "Multiversal Tournament"
idea was explored in a fan-made Dragon Ball Spinoff
like 6 years ago.
Don't forget that Toyotarou is the guy that invented
Dragonball AF, and Toriyama found his work so
similar to his that he got him for the manga
So keep an eye out on all these fan-made things
Because Dragonball the series could get influenced by the fans
(There's a fanmade one that got Goku to get his body
taken over by somebody else and Uub had to kill Goku
Super dark and grimy)
. IDK how you cant be excited about that.
