People play fighting games to fight other people. There are a lot of people, and frankly, I'd say most of them that play exclusively with other players. Why? Their skill lies in improving as a player. There is no benefit to them playing a 'challenge mode' against the CPU, or some weird modifier mode against their friends. That stuff is fun to dick around with your friends who probably don't play as much as you, but at the end of the day, that doesn't help the seventy-five percent of players who play to improve and work hard to do so. And also, it's all limited. People can play multiplayer versus games until they shut down Xbox Live, or PlayStation Network. What do you get with a challenge mode? You beat it a few times and you're done? Or, it's fun for a few spins, but it eventually loses its charm because it's limited replayability.
I understand what you're saying, but my question is: WHY is that the case? MK never really had story-focused games (Konquest mode was always pretty terrible) until MKvsDCU, which STILL wasn't anywhere near as good as this most recent MK. I think devs should, perhaps, start shifting their focus. No one really cared about story modes and then MK came out and proved that you CAN have a somewhat compelling story mode that's a great value proposition AND throw in 300 missions that aren't really about fighting the AI as much as they're about overcoming the weird effects that the mission imposes upon you. And frankly, you say Capcom CAN improve their training modes, but WILL they? My money's on "No."
With online modes against other players, it's always different. If you have one character that is played by fifty different people who play that character twenty different ways, then that's a lot of different, varied matches available. Just multiply that by the number of characters there are in the game.
Oh, don't misunderstand me. AE is fucking garbage. I don't know who they think I am, trying to get me to pay money so they can nerf the fuck out of my character and make way for bullshit shenanigans by the God Tier newcomers. Super is where I stopped as that addition was definitely welcomed.
So I guess at the end of the day I have to say that you're probably right and that Street Fighter is the better fighting game (though the endless iteration is getting a LITTLE tiresome, isn't it?) but Mortal Kombat is the better overall game.
And, what I think you mean to say is that Mortal Kombat is the better overall single player experience, haha.