This card has a solid home now in Winifred Habbamock. In fact, I would say it will be a core card for her.
1) Wini can commit this to any test, meaning she only needs 1 other card committed to get her 2 card commitment bonus. Basically, Wini loves having Wild icons in her hand, and Opportunist has one, so that's a point in its favour.
2) If that test succeeds by 3 or more, she gets this card back in her hand. In addition to the card drawn with her investigator ability, getting Opportunist back prevents her from reducing the raw number of cards in her hand when she commits 2 and draws 1 in return. This allows her to continue to use her ability multiple times a round. Think of Opportunist as fuel for her ability.
3) Wini can easily succeed by 3 or more, because she tends to overcommit anyway. Especially true if she uses this on an Agility test! This means you can feel a bit better about using this card, knowing you'll actually get it back.
4) Wini can very successfully lean into the "succeed by X" Rogue archetype meaning that Opportunist is often not the only effect being triggered on a big success.
Overall, while this card is not as great on other investigators, it is really amazing for Winifred specifically.