I'm mainly playing as a tank Marauder with Blood Magic, loads of health and health regen stuff and some 2hand damage bonuses. On ruthless act 1 at the moment, and I've been using this axe since early Cruel act 2. It kills every basic enemy in one hit, as I use Heavy Strike combined with Added Fire Damage + Increased Elemental Damage and Stun support gems. Then I also have Sweep combined with Increased Accuracy and Life gain on Hit (heals me really well against groups of enemies), Dominating Blow with Added Fire damage and Increased Elemental Damage, Rejuvenation Totem, Molten Shell, Anger aura and some other spells. I have +800 max hp, I regen probably around 60-100 hp per second with my regen totem, I have a flask which heals 1080 HP over 10 seconds, 3 flasks which heal 480 hp over 7 seconds, and a Granite flask which gives me +10000 armor and +24% increased resistances for about 5 seconds.
Needless to say, I refuse to die to almost anything and I still deal tons of damage.
I also play a Templar Summoner, with Zombies, Skeletons and Dominating Blow. Unstable Minions and Necromantic Aegis, Wrath aura (lightning damage) and a rejuvenation totem. The zombies have also Added Lightning Damage and Melee Damage on Full life (Regen and energy shields help to keep this up) and my skeletons have Added Lightning Damage. It is quite cool too, especially with Vulnerability curse. Enemies that aren't resistant to lightning tend to fall quickly to my personal army.