A very fickle question. Let's start with Gluttonous: The Devil's Mistake.
Jethuun would want all demons to be gone for the sake of the universe. However, since he's also demon, and his friend Andy is successfully merged with a demon, they'd disappear too. He'd probably just wish for the general and his armies to disappear.
Marcus would wish for humanity to have the power to fight against the demons, but this would offset the power balance in our universe, thus Earth would be targeted by the celestials. As per our story's current volume, he doesn't know that yet.
Andy would wish for infinite energy to endlessly use his golem powers. His biggest weakness right now is his limited output. He's very strong, but it's a short-lived power.
Now for the Techromaster: Science Incarnate characters.
Dante wouldn't want to use the wish. He dreams to know everything, but he knows the adventure is the best part of learning. He'd save the wish until something irreplaceable breaks, or something he can't obtain presents itself and use it for that. "A good scientist makes his own dreams come true!" As Dante would say.
Genesis would want to wish for Dante's insanity to be cured, but that wouldn't be something Dante would want since it fuels his absurd creativity and caution. So, she'd save the wish for a situation where Dante may die or if something catastrophic happens. "Whatever Dante said!" As Gen would also say.