How to create a filled in Linetype?
For the solid-filled one, you can define a Shape with closely-spaced lines filling it for a solid look when plotted in a lineweight at least as great as the infill-line spacing. Or you can look for a .TTF font character and use it as a text inclusion.
For the connecting, unfortunately a Shape can't curve. Define the linetype, and the origin and perhaps the orientation of the Shape, so that the point of the arrow is the "insertion base point" of the Shape along the path.*
It would be possible to approximate a curvature in the arrowhead itself by making a series of shapes breaking it down into pieces -- maybe I'll post an image of what I mean later.
EDIT: Like this:
* For that, here's one I have that works that way [with a different arrowhead shape, in fact a text character in this case, but the same would apply to yours]. The tip of the arrowhead is always on the path. It still has "issues" on tighter curves, since the Shape must aim in the direction that the path is aiming at its insertion point. That's never an issue [in fact it's a necessity] on a straight path, but note how it looks OK on the outer Circle, but gets more skewed-looking the tighter the curvature.
There's nothing that can be done about that -- it's just in the nature of how shape- or text-inclusion linetypes work.
