Steven Universe - "I like to think that Pink Diamond loved her humans and liked to spend time with them.."

I feel like the more we humanize Pink Diamond and make her the purest of cinnamon rolls, the more tyrannical an cruel she'll be when we finally see her on screen.

Yup, exactly. Pink Diamond wasn't the pure little gem peoples seem to like to think she was. She took those humans from their families, wanted to destroy their planet to make her own colony. If she really had some sort of affection for them, it was the affection you have for pets, not friends or loved ones.