Compbros
Man of Tomorrow
Flash would be the only one to truly beat him. Cyborg? Come on my man. WW would put up a fight but would eventually die. MMH and Aquaman, same thing. The JLA is far from balanced. Superman (pre-New52) was near god mode w/a handful of people being able to actually beat him realisticall. The writers dumbing down some fights in his opponents favor doesn't make it realistic
Cyborg can EASILY construct a device that outputs Red Sun rays which strips Superman of his powers unlike Kryptonite which just leaves him sick. Wonder Woman is faster in combat while Supes is faster running, she practically has his durability and strength on top of wielding magic items with no glaring weaknesses. MMH can mess with Superman's mind, something he can't defend against, on top of being nearly as strong as Clark, super fast, intangibility and telepathy. Aquaman has high endurance, hydrokinesis, a magic trident and super strength. Near God mode? Early on, without a doubt but he is no where near as Godly as he used to be and would get his ass handed to him regularly.