This is my take...
PENIS SHAPE:
PROW: A "prow" is the front part of a ship where it curves up. So I would say that if you have an upward curve or a banana curve, then you would have a prow shaped penis. For this piece, I will call an upward curve a vertical prow. Consequently, if it curves to the left or right, then it could be construed to be a horizontal prow.
STRAIGHT: Self explanatory. If you do not have curvature then you have a straight penis.
GLANS SHAPE:
SLEEK: Glans is similar in size as shaft. There is not a big lip (sulcus) behind the glans.
Helmet/Blunt: Glans is uniform with shaft and ends in a rounded tip. A helmet will have a bit of a lip/sulcus.
Arrow/Spade: Glans is uniform with the shaft and ends in a more point. An arrow/spade will have a bit of a lip/sulcus.
Rocket: Glans is smaller than the shaft and may seem to just be a tapered end of the shaft. There is barely to no lip/sulcus to a rocket.
EXPANDED: Glans is bigger than shaft. There is a large lip (sulcus) behind the glans.
Mushroom/Bottle: Glans is bigger than shaft and ends in a rounded tip. The shaft will taper down near the end, but the glans will be approximately the same size as a shaft section a 1/4th of the way back. Bottles may be slightly boxier than a mushroom.
Club: Glans is bigger than the biggest part of the shaft or considerably bigger than the neck/mucous membrane of the shaft. The width of the glans is wider than the widest part of the shaft when viewing from the side and above.
For comparison, I would say that the penis in the original post by chuckman2 is a Rocket-Arrow. Unabear09 with a Blunt-Helmet. Charles Finn seems like he may have a Mushroom. Yorkie with a Spaded Helmet. Fiker with a Blunt-Helmet (with a frenulum). Westcoastberry with a Mushroom. BigmeatNJ seems like a Mushroom-Bottle mix. And I would say that Slate_australis is a Bottle-Helmet.
LOL, does that make any sense? But then again, what do I know?