Hello,

It looks like some of the edges are racked and you have a few little edges that can cause you problems. Using your model as reference model, I started with some rectangles at the corner points, filleted those rectangles, then used the blend tool to blend the construction lines together to form the edges of the and then swept the surfaces (you could use network in some areas as well if you find a better result). I joined the swept surfaces together to form a joined surface then used the NSided command to patch that hole. Having less points helps you sometimes because it makes modification easier down the road. Little tiny tweaks and many points do not usually help you like they might in a poly modeler.