The game went on sale for $8.99, so I picked it up.
In terms of what is unlocked by default, not a lot. Just the DLC skin packs, as well as the mobile skins. That's a shame, as I'd assume that, like Mortal Kombat: Komplete Edition before it, all the skins would be unlocked by default.
I do believe Shinnok was unlocked though without needing to play through Story Mode.