If enemies have been marked, then as DPS I'm supposed to target enemy #1 until it's dead, then enemy #2, etc. The problem I'm having is that if enemy #1 dies quickly, I want to know that #2 is up next.

Currently, even after a mob dies, any sign placed on it (like "1") still shows on the screen. Of course, it shows up next to the body of a dead mob, but if it's in the midst of a big jumble of mobs and players, that's not always obvious. So I'm left still cycling through mobs, hoping the one with that "1" sign comes up targeted, and of course it won't since it's already dead. If the sign would disappear immediately on death, then it would be far easier to see that #2 is up next and that's the one I should be trying to target.