That's true. Batman would easily take Superman. I remember reading some story line where Superman actually gave Batman
Kryptonite just so Batman could take superman out if supe ever went out of control or something. Even in a world where no Kryptonite exists the bat would find a way. One of my favorite graphic novels was "The Dark Knight Returns".
Doctor Doom would beat them all at the same time. He has countless gadgets like a time machine, nerve impulse scrambler, etc. Doom is also one of the most powerful practitioners of sorcery. If anyone did take him out it would just end up being one of his Doom Bots. If he did run into any trouble he could just get his hands on the Infinity Gauntlet and/or gain the Beyonder's powers again.
Although, the true winner of the Ultimate Showdown of Ultimate Destiny is Mr. Rogers in a bloodstained sweater.