"FFVII Reunion" is a good name, and not overly wordy for the sake of it, although I would prefer simply calling it "Final Fantasy VII." Using the original name is fine - look at the Tomb Raider reboot. As long as they market it properly - and it will market itself, anyway - it will be fine. The only issue right now is the current re-release of the port to PS4. Once the remake rolls around, though, the original name will be fine for the remake. "Reunion" is effective, though.