Yeah I would honestly say that staying power depends on two big things: 1. DC pushing the character in various mediums and 2. People continuing to read/support said character. Look at a character like Jessica Cruz, literally the 6th Green Lantern Corps member from earth when we already had established another new green lantern in Simon Baz. But guess what, DC pushed her in multiple comics, put her in animated movies, cartoons for kids, and apparently now a video game based on said kids cartoon. All it takes is a little backing and fan support and any character could potentially be popular.

For all we know if we support Jace enough he could do well for himself, maybe get an action figure or an animated movie. Whose to say, but I just don't think you can just count a character out, especially when this is only his origin mini-series.