A creative writing exercise for everyone if interested. What would your characters power level be at the absolute maximum of this RP? Create a skillset for your characters at the absolute strongest they can ever be, even Miyu can be god levels of strong if you really get creative.
For Henry I see it going one of three ways. One he maximises his ability with the Gates of Tartarus, swallowing entire planet's into his collection and then shooting them at foes in battle. Maybe even an exploding sun or two for when things get serious. Two he maximises his Silver Eyes, creating Gurren Lagann levels of mechs, blasting foes away with enough energy to destroy planets. Finally he maximises his skill with the Cheater's Blade, slashing through entire planet's with one blow or cutting an opponent's very existence away. Which would obviously be very tiring but effective.
What about you? How ridiculous could your characters get?