Как правильно составить иерархию классов\интерфейсов?

public class MG_Drawing implements MG_I_Drawing {
    public final ArrayList<MG_I_DrawingElement> elements = new ArrayList<>();
 
    @Override
    public void addElement(MG_I_DrawingElement el) {
        this.elements.add(el);
    }
 
    @Override
    public ArrayList<MG_I_DrawingElement> getElements(){
        return this.elements;
    }
}
 
public interface MG_I_Drawing {
    public void addElement(MG_I_DrawingElement el);
    public ArrayList<MG_I_DrawingElement> getElements();
}
 
public interface MG_I_DrawingRenderable extends MG_I_Drawing, MG_I_Renderable{}
public interface MG_I_DRElement extends MG_I_DrawingElement, MG_I_Renderable {}
 
public interface MG_I_Renderable {
    public void render(Graphics2D g2d);
}
 
public class MG_DrawingRenderable extends MG_Drawing implements MG_I_DrawingRenderable{
    
    private final ArrayList<MG_I_DRElement> elements = new ArrayList<>();
 
    @Override
    public void addElement(MG_I_DrawingElement el) {}//это не подходит
 
    @Override
    public void addElement(MG_I_DRElement el) {}//на это ругается
 
    @Override
    public void render(Graphics2D g2d) {
        for (MG_I_Renderable rEls : this.elements) {
            rEls.render(g2d);
        }
    }
}

public class Demo {
 
    public static void main(String[] args) {
        MG_Drawing d = new MG_Drawing();
        d.addElement(new MG_DrawingPoint(10, 20, d));
 
        for (MG_I_DrawingElement el : d.getElements()) {
            System.out.println(el.toString());
        }
    }
 
}
 
interface MG_I_Drawing {
 
    public void addElement(MG_I_DrawingElement el);
 
    public ArrayList<MG_I_DrawingElement> getElements();
}
 
class MG_Drawing implements MG_I_Drawing {
 
    public final ArrayList<MG_I_DrawingElement> elements = new ArrayList<>();
 
    @Override
    public void addElement(MG_I_DrawingElement el) {
        this.elements.add(el);
    }
 
    @Override
    public ArrayList<MG_I_DrawingElement> getElements() {
        return this.elements;
    }
}
 
//class MG_DrawingRenderable ...{
//...
//}
//
interface MG_I_DrawingElement {
 
    public void setDrawing(MG_I_Drawing d);
 
}
 
abstract class MG_DrawingElement implements MG_I_DrawingElement {
 
    public MG_I_Drawing drawing = null;
 
    public MG_DrawingElement(MG_I_Drawing drawing) {
        this.setDrawing(drawing);
    }
 
    @Override
    public final void setDrawing(MG_I_Drawing d) {
        this.drawing = d;
    }
}
 
interface MG_I_DrawingPoint extends MG_I_DrawingElement {
 
}
 
class MG_DrawingPoint extends MG_DrawingElement implements MG_I_DrawingPoint {
 
    int x;
    int y;
 
    public MG_DrawingPoint(int x, int y, MG_I_Drawing drawing) {
        super(drawing);
        this.x = x;
        this.y = y;
    }
 
    @Override
    public String toString() {
        return "(" + x + ", " + y + ")";
    }
 
}
interface MG_I_DRPoint extends MG_I_DRElement, MG_I_DrawingPoint{
    
}
class MG_DRPoint extends MG_DrawingPoint implements MG_I_DRPoint {
 
    public MG_DRPoint(int x, int y, MG_I_Drawing drawing) {
        super(x, y, drawing);
    }
 
    @Override
    public void render() {
        System.out.println("точка "+super.toString()+" отображена.");
    }
    
}
 
interface MG_I_DrawingRenderable extends MG_I_Drawing, MG_I_Renderable {
 
    public void addElement(MG_I_DRElement el);
 
    public ArrayList<MG_I_DRElement> getElements(String groupName);
}
 
interface MG_I_Renderable {
 
    public void render();
}
 
interface MG_I_DRElement extends MG_I_DrawingElement, MG_I_Renderable {
}