I find that an odd way of thinking Gmd, you get like 99% of the hours out of an FPS from the multiplayer compared with SP. Not having a single player just loses 1% of content.
There's also 3 game modes, payload, capture and king of the hill. Aside from that there's custom games and there's the challenge mode which changes weekly.
Aand, blizz don't really change prices £30 is what it'll cost for the forseeable future.
@Jub, Creating characters people want to play means that you have to create backstory. It's generally regarded as to why Battleborn and the like haven't done as well as Overwatch, the lore is paper thin. Also I feel like singleplayer story might come out as separate DLC somewhere along the line.