That's more of an issue with Absolution than the Goblin. It's entirely possible to reach level 4 with only killing a handful of monsters if you've got a strong class at your disposal. Still, definitely a nice combo for the goblin and it works with any class and level, even ones where leveling up is tough.
Still not sold on conversion stone with a goblin on a vicious level; seems a steep price to pay once you're level 10 or higher, which is a forgone conclusion on vicious levels.