If you live within their range, it is usually not hard to attract Northern Cardinals to your feeders. Offer them what they like to eat in feeders they prefer and create a welcoming environment in your yard.
Attracting Blue Jays: Blue Jays are fun birds. Members of the Corvidae family, they are smart and bold. Yes, they can seem a little obnoxious to human eyes. But if you watch them, they don’t so much bully other birds at the feeders as behave in a loud self-important “me first” way.
They fly in, take what they want, announcing it with loud calls, and then move on to other business. And sometimes other backyard birds call their bluff and they are the ones who have to back off! Would you like Blue Jays in your yard? Offer them the foods they like!
In our suburban Maryland yard, a pair of Fish Crows nested each spring/early summer for several years. Many of the other birds were not that crazy about the Fish Crows. I understand they sometimes will eat the eggs and nestlings of other birds. So I do understand the animosity.
But even so, I must admit that I really like Fish Crows. They are some of my favorite birds in the yard. They are smart and social and will sometimes interact with me (when food is involved) so I enjoy them and encourage them in the yard.