You want to build tainted/fire warlocks and get gear for those as early as now as they will become the top tier for when they apply the patch. The ES warlock in PTR struggles with player 8, ubers, and colossal ancients, though there are alternatives like putting more hexes or mirror blades, but still not strong as it use to be, the nerfs really killed it. Do not buy those expensive 30 fcr ars meph books or bone breaks, not worth the price, for a build that is basically done