It still wouldn't last very long. The movie is here for the exact purpose of explaining stuff and acting as a huge throwback at the original series.
Also, YGO used the right formula to stay alive, keep changing the generations to keep it fresh. The fact that the last two sucked is a different topic alltogether but the point is, its better not to drag out the original and ruin its great ending just for the sake of older fans (wich will be displeased if their fav series is ruined) who don't want things to change.
Now, about the rumors of this not being connected to the anime. Nowhere was it stated that this is an alternate (manga canon) movie. It's just made to commemorate 20 years of YGO manga (just like how Bonds Beyond Time was there to celebrate 10 years of anime), but the story shouldn't be exclusive to manga (wich is pretty close to the anime, but with a few twists as you pointed out). The 5DX theme has already been played out pretty well, so a good quality continuation like this would be a much more valued experience then manga-exclusive story.
I'm just worried about the title because it hints greately at Arc-V, wich is a huge problem. I hope it has nothing to do with it, because that series sucks big time.
Put a mark there going "my opinion" because 5D's was acclaimed almost as much as the original, the only downfall being a too big change with the motorcycles and the fact that it's a spin-off. It's story and characters are downright on par with the original, and even excel at certain parts.
Also, Anubis was crap, the real deal is Bonds Beyond Time. And Never Ever watch YGO in anything but the original. The dubs ruin it so much its a criminal act.