Let's be direct, I hope you don't take it the wrong way:
This was a very good idea with poor execution.
1.- Gameplay: this is clearly inspired by Summer Memories, you can tell by the interface of the minigames, however, it is very tedious that during the minigame you are interrupted every 2 clicks to show text, not to mention that there is nothing to do More than clicking and playing the mini-games but it gets repetitive very quickly.
2.- Story: there is none, everything is summarized in you have mini-games collect "points" and buy perks, but there is simply almost nothing in the story, according to the plot this would be a trainer but there is little of that.
3.- The MC: seriously? Krillin? If this is a trainer, it is clear that Roshi is the best option, even the story writes itself. Example: Roshi wants to corrupt n.18 but it is clear that she rejects him so tired of that, he uses the spheres and gets a way to "train" her, during the game you simply have to be careful because if Krillin notices that = Game over, if you go very fast with n.18 = Game over and in addition to training her Roshi would have to look for ways to get money and obtain "accessories" to their work, and even girls like Chichi, Bulma and Videl could be added in the future.
It's just a tip, but I think it would have greater potential.
P.S. If anyone wants to reuse this poorly made story that I just shared, do it, you need a good trainer like that.