I'm almost done with the game with the similar build as yours. But you can't just survive in act 2 wirh Warfare and Necro alone. You'll need Scoundrel for Adrenaline and Cloak and Dagger, Hydro for Restoration and Armor of frost, Geo for Fortify and Huntsman for Tactical retreat. Also Poly for Skin graft, which combines well with adrenaline, and for Chameleon cloak. I also used Pyro for some damage against opponents that use evasion aura (at least one of them on Bloodmoon isle) and for Haste and Clear mind.
The beginning of act 2 was very tough for me, I couldn't have survived wirhout those skills. You should also put skills in thievery and try to steal as much gold as possible from every character you meet. This way you can upgrade your gear every level, which is the only way to stay viable against enemies. The alternative is lucky charm.
