I think what you meant to say there was that MK4 was a return to form after the series faltered massively with every version of 3, and Mythologies which is one of the worst platformer/beat 'em ups I've ever seen.
With MK4, they dropped the silly dial a combo nonsense that they began with 3, cut down on the number of superfluous special moves, sped up the game substantially, and threw out all of the silly nonsense finishing moves in favour of having 2 really done fatalities each and stage fatalities. MK4 is, in many ways, a better successor to MK2 than any other game in the series aside from the reboot.
And campy as hell cut scenes and laughable voice acting just make it that much better.
And Forsaken Lover, you're missing out if you don't play the reboot. Hands down the best MK title if you ask me. It's closer to being an enjoyable fighting game then any of them, and all of the best violent bits are completely over the top and absolutely delightful.
But one MK that never gets talked about nearly enough is Shaolin Monks. That game was damn brilliant I must say.