Good post, you've pinned down the issues with a remake. Very difficult to recreate a moment in time, a 'feeling', if you were going for a '70s style film.
Using period correct film stock with Panavision cameras and 1970's Production Designer, Cinematographer/DoP, etc would help with the look. Composer Barry De Vorzon is till alive for the score.
A modern day version would be an easier production and find a wider audience.
Casting would probably demand all nine gang members be 'names' which may or may be a good thing. I would be interested if it ever did happen.
I think Ralph Bakshi could still manage an animated sequel, with the original cast being Rotoscoped and doing the voices. Doubt anyone would want to finance it.
I liked American Pop with its '70s set New York segment.

The Warriors - '79
is so rooted in graphic novel origins, that Hill gave his film a heightened and dizzy sense of stylized urban color and neon reflections. It was like an alternate universe, or even a purgatory (or heaven), for gang members. It was also quite original and born of its time too. It even had a late 70's gritty filming quality about it.
A remake would have to be its own film to stand alone, and it could also be a rare instance where "wokeness" might work, because it could be exaggerated and satirized being set in a colorful gangsta's paradise.
It would need to know its style and substance and make it consistent throughout. The only problem with these remakes, or for those that have the point of references, is that they can seem tired, as in seen it all before.
Norman! What did you put in my tea?

Lol, sounds like something Quentin Tarantino would make if he was slumming it on the SyFy Channel.
Not 'The Trannies' but there was a gay gang called 'The Dingo's' in the original film, all black leather, studs and Doberman dogs on chains. They captured one of the Warriors, Swan I think, and were going to rape him.
This was all cut from the final film but you can still see them at the meeting scene.
Original character design.

If they do then either take it in a serious direction with normal looking gangs or else take it in the other with even more silly looking ones and concepts.
The Bozos.
They all dress up like clowns with full make up, red noses and orange frizzy hair.
The Zombies
Great make up jobs make them look like the walking dead.
Bigfeet Gang
Faux fur outfits make this gang look like the shy ape man who is rumored to live in the woods of northern Cal.
The Gandhi Gang
Shaved heads, round glasses, and they even dress like the non violent leader and they never strike back at their opponents. Which makes them an easy target and why they are down to the last two members.
The Feminazis and The Trannies
Since movies have to be woke now they have to feature strong willed women and those who are confused about the gender they were born with.
Aliens
No, not illegal ones. The kind that come from outer space! Literally! Their weapon of choice? What else butt anal probes!
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