I agree it seems like it would be a natural for remastering in hi-def format because:
1. The wide-screen format that made it a theatrical-release orphan in 1971 would work well on home big-screens in 2015.
2. The post-SHTF/Mad Max/collapse of civilization genre is much more in tune with our times than it was in 1971.
3. The John Barry soundtrack was epic. If the film had been made in a regular-width format, and it had found initial success, the soundtrack would have helped to carry the movie and vice-versa.