Ant-Man and Wasp are pretty much the Aquamans of the team. Their powers are silly and they don't have very interesting origin stories. Ant-Man even talks to insects like Aquaman talks to fish. While I like the characters, I'm not sure how well a movie with those two will do.
Aquaman is infinitely more popular than Hank and Jan, but JLU still replaced him with Hawkgirl.
Of course, they could go an entirely different direction with this movie. Blade was pretty forgettable in the comics until the Blade movie producters turned him into a badass daywalker vampire hunter played by Wesley Snipes.