If you are missing an integral piece of the puzzle that is preventing you from being successful, in your case an employee that can design, you will have a hard time becoming successful without one in this line of work.
If you can handle your responsibilities as a business owner, a good solid designer will pay for itself (and then some). Two heads are better than one. In this business it really does help to have full access to a good designer.
Maybe look for designers right out of school. They won't be the best at first, but if you help them and give them the tools to grow, your business will grow along with them.