It honestly comes up with great scenarios to throw the DC characters into. James Woods voicing Lex Luthor getting the power of Zeus is just the tip of the iceberg.
You got Firestorm vs. the Nuclear Family, the classic Superman under a red sun scenario, Batman and Etrigan fighting a possessed Demon batmobile, A Randy Savage Lobo tricking the Justice League into fighting the Red Lantern Corps., Cain telling a story about Zatanna, Constantine, Batman and Doctor Fate turning into kids and escaping the House of Mystery, and it just goes on and on with great concepts.
Then it executes them well with clever writing that is funny but actually respects the characters they use and good action. Firestorm actually transmutes stuff, and they use super obscure characters from the comics you would only know about if you actually read and cared about the comics. Not to mention lots of people working on it worked on the original Justice League cartoons and it shines through, even in the sound design during fight scenes.
Honestly they shouldn't have been able to make an action cartoon this good with the budget they were given. They could have been lazy like Teen Titans Go and saved on animation costs by turning into a sitcom with retarded humor but they actually gave a shit and made a surprisingly enjoyable show. I like it even better then Young Justice. Yeah it isn't dramatic and on the whole it's pretty shallow in the plot and character development department. But it's fun as hell and it's executed well with clever writing and smart designs that let them animate good action on a tight budget. It isn't just about being better than TTGo.