The problem isn't everyone but Superman.
The problem *is* Superman.
DC/WB is determined to return Superman back to his Silver Age silliness where he is the best at everything. He is the strongest, he is the toughest, he is the fastest. You can't even allow for Speed Force bullshittery to overcomes Supes.
The best thing that could ever happen to the DCU, for both Supes and all non-Supes characters, is if he were redefined to not be susceptible to power creep. IMO the way to do it is to make Supes super at *everything* but not the best at everything. I'd be willing to expand his powerset to all sorts of stunts but turn him into a Jack of All Trades, Master of None.
Fast, but Flash is faster. Strong, but (Wondy? Barda? Arthur?) is stronger/tougher. Give him more sensory powers, more energy-based powers. None of which are the best of the best.