TamaTsuki: A Fox Tail and Blood Moon of Lies

I am again writing a story of Fate. This time the heroine is, as you guessed, Tamamo no Mae. I just played Fate/Extra and as waifu I chose her. She was hard to raise but so OP in the later stage plus if you add her back story that takes your heart away~. Anyway, I have no idea what powers I should give to MC. I don’t know if I should add Minamoto Raiko and her children in series with Raiko as harem member. Or I am even thinking about adding Arcueid but who knows. Suggestions are welcome.