No argument there.
Young Justice is easily my favorite DC show after Batman the Animated Series, I'd argue it's better than the great Avengers show it challenges, despite my nitpick, and that it ends with a dangling plot that clearly stands out like a cliffhanger, something we will never see resolved.
You should give it a watch, but be warned [blackout]series finale ends with Wally dying (maybe?), and Barry surviving,[/blackout] so that will probably piss you off.
Just so it won't catch you off-guard if you decide to watch it.