The Oak can always use more art and articles. If you aren't comfortable with your writing ability, the editor would be delighted to work with you. Space in The Oak is limited, and the people of Atlantia have a wide range of interests. It's better to acknowledge those interests by printing a number of short articles on a variety of topics than devoting a whole issue to a single subject. Focus is good.
Brief articles are usually more effective when they focus tightly on a topic.
C.E. Illustrations are good. Written instructions are easier to follow when accompanied by pictures. If you can't draw, see if you can talk an artist friend into helping you out. Documentation is good. Demonstrate the relationship between your work and a medieval subject or activity.