I believe the warlock is good where its at for a while... I am going to switch to only be playing as an embermage for a while, and going to start looking at altering the class as needed for the content and enviroment we play in.
I'll try a billion builds to see what works and what doesn't but expect to see some alterations.. I'll likely be reluctant to change anything that changes how the class works completely, but we'll see where it goes.. I'll also post here about things as I go if I am considering but not sure of it.