You don’t hire professionals or contractors based on the business card, you hire them based on the fascinating conversation you had about design, or marketing, or the tax implications of LIFO inventory accounting. The business card is a visual and tactile reminder of that conversation; a month or six later, when you suddenly realize that you need a designer, or a marketing consultant, or a new accountant, you remember the conversation, remember that the savvy businesswoman gave you her card, flip through your small collection of cards, and there it is – a slick 3.5" x 2" ad, reminding you of her name, how you can contact her, and that yes, you have the right card, because it tells you exactly what she does.
I’m a 20+ year veteran in sales and marketing, but you will quickly learn in the industry that years does not equal quality, so YMMV.
Sales is storytelling and the PR and design part of marketing is creating and illustrating stories (and yes, I know this is a gross simplification).
What is your story? You want the person to look at your card and remember what one message? You can never, ever expect a potential customer / client to love you as much as you do, so always simplify. (Which is a simplification.) As other have pointed out, it’s not the card which will sell you, it’s what you say. The card will only help them remember your conversation.
People will not be hiring you for your years of experience. New talent gets hired because we expect them to grow, and we look for potential.