The violin intro, as heard on the kurenai pv demo videos, does sound great, but its just a different version of the chorus. The original acoustic guitar opening played by hide (and Sugizo can easily play it too) has a completely different composition to the chorus and the rest of the song, its an iconic/memorable opening, just as much as led zeppelins' stairway to heaven is, you can't just replace it with different version of the chorus.
Not only that but according to that pv preview, Toshi's first chorus "I couldn't look back" ect. is getting cut from the song too.
This of course all depends on wether that was just a demo of the song or not.