Reincarnation in DxD with wishes

Should I turn this story into a harem story? If I do, who would you prefer?

What other powers should be given to the main character? I'm thinking of giving powers like the Shadow monarch or Escanor.

Should there be a crossover with another universe? For example, Devil Testament Sister New Devils, Oregairu, or anything else?

What else would you like to see in this story?