So, I was waiting to make this prediction until something relevant to it happened, and I guess "Stella officially decides to join in on the search for Oriko's mother" is good enough - how much do you want to bet that Oriko and Stella are actually (half) sisters, and Stella is unknowingly joining in on the search for her own mother as well? After all, Oriko's mom is a "natural giantess" just like Stella, is currently in space, had already left Oriko for space at the time Stella would have been born, and has an established track record of abandoning her kids at young ages, which tracks with Stella's backstory of having been found by Gimlet abandoned as a baby.