personally I definately think yes, but only if his persona was the one from the original movie. I want him mean and ugly. The second one was too cute and friendly.

Also, I would prefer it if slimer remained an enemy of the Ghostbusters. A pest that roams New York in search of food. The one ghost they cannot catch because he's since got smart after his first entrapment.

he was friendly in the second because thats what ended up being of him throughout the cartoon series.

no point really asking if we would prefer slimer in the 3rd because noone will be in the third.