Ono has promised multiple times that SFV will be more competent in the story department. What will make you guys happy with SFV's story and single player content?
Street Fighters gone by seem to have settled with a single-player experience consisting solely of a fight-to-the-boss arcade mode.
Personally, I'd like to see them expand on storylines set up from the UDON comics. Capcom has a surprisingly rich canon that they don't do anything with and that's really unfortunate.
I'm not asking for Netherrealm style chapter based story telling, but I would like to see a cutscene here or there with a sense of direction and motivation for characters instead of going from one fight to the next.