Invulnerable Minion packs have been very challenging for me while soloing Hell.
Generally I've been using Haunt and Poison Darts with Splinters for my single target damage, but Splinters tends to get blocked by the invulnerable minions, making positioning very important.
I'm not looking for specific builds, but rather specific tactics for a variety of builds, so that I can pick one to match whatever build I'm using.