Oh, this is easy for me. I’ve been wanting this since 2016 (and have been mentioning it from time to time). I would love a Tempest: Year One mini. Garth’s PE history is filled with mystery. He had appearances pre-Rebirth as a member of The Drift, and then after Rebirth, he was with the Titans until No Justice. During Titans, he talks about how he went to then Silent School to learn magic and how he lost someone close to him during that part of his life.
I would love a story that touched upon his actual origins. Is he still an Idyllist prince from the Hidden Valley like in NE, for example? Was he cast out? Did Arthur find him? If not, who did? How did he get to Atlantis, is another way to phrase that. What was his relationship with Tula (I want it to be PE canon that they at least once had a romance since their relationship was pivotal for both characters in NE)? How did Garth join the original Teen Titans in PE? After the group disbanded after being mind-wiped, is that when he went to the Silent School? What happened in the Silent School? Who was the loved one lost? What is he doing now? Is he still with Omen?
A flashback Year One tale for Tempest would answer a lot of unknown questions.