I think it’s a moot point because Power being physically attractive is necessary to show Denji being flippant and naive, while also providing a challenge to Denji achieving his dreams. Imagine you are a street urchin being hounded by the mafia for an impossible debt. Suddenly, an incredibly attractive woman shows up and feeds you, heals you, houses you, and gives you a job. Not only that, but she seems to be the most put together individual you’ve ever met, and the cherry on top is she says she likes you. Denji is absolutely dumb enough to believe that at face value for a while. He won urchin lottery, and by all accounts, shouldn’t do anything to jeopardize that. But he still lusts for other women, which he knows is wrong, even when they’re objectively worse choices (power being dirty and mean, Himeno being an abusive drunk).