I wasn't actually thinking of a game to be honest, I should have made myself more clear. Still, I think a film would actually do well (preferably animated so SE doesn't feel obligated to add Wire-Fu or "wow" moments) as I don't see the story needing to go into too much detail with some characters as most of the VI cast will most likely be children in this time frame not to mention characters like Cyan wouldn't be doing anything terribly important.

The only issue would be whether to use it as a platform for telling Shadow's story. I'd personally rather not deal with it as I feel the game details his past in a way very fitting for the character. Too much detail would ruin the allure of the character. So I feel if we stuck mostly to Terra, Celes, Kefka, Cid and Leo; it could build a strong story narrative and leave the other characters to simple fan service shout outs.

Though thinking about it more, I could see a game being built around the scenario, just make sure not to make the same mistake as Crisis Core and try to build it into some "grand adventure that took place before the other grand adventure". A game focused as a character piece exploring these five characters could make a compelling story even if the title didn't have a major villain or major world shattering conflict. The real drama for the player would simply be knowing how it would all end when it finally jumps into FFVI.

I think this has been the major weakness in all the sequels/prequels SE has made is that they try to write stories that are considered to be on the same world crisis scale of the originals when I feel a simpler character piece would satiate most fans.