There was a thread on this, but it accidentally got deleted when I tried to delete the old PDF specimen with a new one, not realizing it would delete the thread and not the file.
Apologies to all those who replied.
Here is, more or less, my rationale and the updated PDF specimen attached below:
In fingerspelling, a handshape indicates a letter, which could be depicted from a range of complex pictoral representations to simple systematic strokes. At small sizes, many handforms (a, e, m, n, s, t) could be relatively difficult to distinguish from. The creation of such a font includes several parameters: the limitation of using only positive and negative space, stroke (and counter) thickness, and how complex or simple the hand, fingers, and detail should be. Since each letter contains more strokes than English characters, it is difficult, if not impossible, to create a highly legible font intended for small sizes. Thus, the use of a fingerspelling font should only be used as display type, for instructional or cultural purposes.
After studying and comparing the subtle differences of the manual alphabet, and what visual cues each hand presents, some important parameters were established. Other than the form of the hand itself, the fingernails are powerful visual cues that distinguishes similar letters, which is also why a bold version could be created. Since the manual alphabet is communicated with human hands, representing the font in human-like forms is easier to pick up than say, hands in thick winter gloves or systematic semi-abstract forms that derive away from naturally recognizable forms. By keeping the bony angular forms of the hand, important visual cues are revealed from the bone structure. With a recognizable form of the hand, excess inner detail can be eliminated and thus, retain simplicity without inducing complexity to maintain legibility. In addition, all of the letters designed are what one would see if somebody in front of you was reciting the manual alphabet, to keep consistency without seeing irregular angles.
Stroke width was a difficult decision to make for the outlined regular version. If the stroke width were to be thick, logically it would be easier to see; however, the bone structure of the hand would lose its angularity and inner detail would jumble together to lose recognizability. In short, the thicker the lines, the less human the hands appear. Nonetheless, since the font was designed for display, the forms remain intact at 36 points in print, at minimum. Since there are two levels of recognizability, the hand as a whole and the inner detail of the hand, the outer stroke of each character is slightly thicker. While each character is complex enough on its own, the stroke width is consistent in size throughout for simplicity. Finally, since outlined handshapes can never be thicker than the English alphabet at a similar point size, a filled (bold) version was created to counter the lack of visual color, but yet still remain legible.