So he might be back.

According to comic book resources Jim Lee said that Ryan Choi may return as the atom in the new Justice League book.

Asked about increasing diversity—particularly, "where are the Asians?"—Wallace said that diversity did not have to only mean heroes, but "diverse people." "When you look at the world around them, it's populated by" people of every color and orientation. He added that there would be an Asian hero debuting in "Mr. Terrific."

Lee added that "there's a character in Justice League—a very small character—rhymes with 'Batom.'"
Hopefully is is Ryan, I really liked him, or DC may be pulling or legs again like they've been with Cassandra Cain.  The optimist in me likes to think that they aren't. The link is below.
Posted by Billy Batson

Good news everyone!