Blood for the Baron!

leatherneck was in the arc where they invaded Springfield, as well as 'Ambush' and the river pirates story in Special Missions. i don't think of him as being a 'leser known Joe'.

Sorry, I didn't know that. I know little about the "Serpentor era" created Joes (even though I know a bit about the s created in the same era). The main mistery (even for myself) is how I know (and knowing is half the chara knowledge) so much about Beachhead, who is from around that same time.

Where there any charactors who where in the comic & never made it into toy-form?

Well, there were Billy, Dr Venom, Candy, General Austin. Maybe Candy ( 's love interest) and Austin (general who ranted orders) were not Action Figure material, but Dr Venom (Mad scientist) and Billy (Arashikage ninja) could have been.

There have also been fiction-only charas who became toys many years later: Fred VII (Siegie who faked to be , two toy releases), General Flagg (the first two figures were his son; the 3rd one represens him but the filecard mistakes him for the son), Kwinn (a honorable mercenary), Scar-Face (a scarred ) and Sparks (a special case; most of the others are based on comic charas, but he was a TV chara).
The thing I don't know is if Clay Moore is or not the who appeared in a given TV episode.

Hollingsworth, Dyson and Ryan

Mangler and Cool Breeze as well

Oh and Mayday a DDP character

Many female charas remain without figs: Dr Biggles-Jones, Dr Knox, Firewall, Pythona...

What about Lightfoot? Did he have any fictional appearance?

Pythona had a figure. or are you on about another Pythona than the Cobra-La one?