Ive gotten to 98 as a bone spear necro. I can already tell that it would be rough for high nightmare dungeons. Infimist is probably the route id take. That or lower my damage and spec hard into fortify. Not sure which would work out better.
I still cant kill Lillith. I can nuke her hard, but if you cant dodge the waves your still gonna fail that fight. I suppose you could get a huge string of lucky hits for essence, but even then, she moves like crazy, and you need good positioning to make your damage work, as well as baiting waves. These streamers are some of the best players in the game, they would be rolling over content regardless of class.