I can see why it ain't everyone's cup.
Sure it was cheap. It was a cost-cutting innovation. But he took those savings and plowed them into some sweet animation, on a budget he could get get in the real world. And it fit the "Oh my god we must censor out all the violence, boo hoo!" times. It's like the shower curtain in Psycho. Told the story, but wasn't graphic. (Animation was considered kid's-first, and boy did they censor it, in the 70's. There was more leeway in movies, but still).
The technical side of this, though, belongs in the "Requests, How-to's, and Technical Discussions" sub-forum.
A bit of advice: honey is better than vinegar. You may feel disgusted, but you want people to come in with positive "That would be neat." thoughts. Maybe change the subject of your first post of the thread to something a little more mellow. Say - "Upgrading the rotoscoping in Bakshi's LotR?".
AE is meant to be frustrating. They want you to take classes, and study under masters to learn their trade secrets. It's built for proffessionals - and "the last thing they need" is a 20,000 self-studied hot shots suddenly competing for their jobs. But that ain't going to happen because there's massive demand from small-scale advertisers, and most people are happy to use their skills to amuse themselves. Thankfully, there's many experts who aren't paranoid, so the info's out there.
But I digress...
It just might be possible to make AE draw a line at the boundry of the colors. And then put the tracings on a monotone.
Since the information is 2-color, there's nothing else to process. So I doubt if you could do more than that without hiring animators.
I only know a thin slice of AE's functionality, so I couldn't tell you "if" or "how".
If it can do that, it would probably work something like an image editor function - you'd auto-trace the boundry onto another layer, and replace the original layer.
A tedious possibility - if you get the lines-on-paper effect, you could manually add some motion blur-effect to selected areas (fast moving limbs & such). Don't ask me how, though.
If you want to spend months on it, learn rotoscoping, and do whatdoyacallit? Radial density? Give them a sense of shape & mass.
Maybe effects-up a swirling fog/dust effect, and use the solid background as your chroma-key color. Give it that fog-of-war thing. (Men and animals stirring up clouds of dust when they fight).
Maybe save the scenes to sequences of images & try some watercolor/oil brush effects in an image editor.
Or buy some plugins, and do it in AE.
You could play with clipping out frames & morphing so the blows look fierce, instead of like inexperienced stunt-actors pulling punches.
Google up tutorials, try forums that are dedicated to that stuff, maybe invest in those here's-what-we-think-you-want-to-know books.
Maybe you can get other people interested in working on the project with you. You might have to get some stuff done, first, and show it to them, though.
It's up to you, learn it, play with it, and show us what you come up with.