From someone who played all the original games, this game doesn't seem to make all that much sense story wise nor does it particularly give me any real interest. I know Lethal's supposed to be practically a demonic overlord according to the series but I just feel that this game dumbs him down too much. The other characters are not exactly memorable either and I miss being able to custom create your own guy to party with. I also don't like how plain and generic you've made the game look but I have to complement your music choices and that you've made it at least user friendly (no more bashing the WASD or arrows to ensure combo hits, thank god).
Overall, I think you have changed the genre but the game is still lacking... sorry if this review comes across rudely but I want to be able to see great games from the lethal series, I really do. Good luck in your future games.