Warpiglet
Adventurer
Another build I like with the Warlock, without going in min-maxing as I know you prefer concept over build, is the idea of a warlock without charisma. GOO and Undying can work quite well for this. Take Self-buffing spells and invocations.
Variant Human for Moderately Armored, GOO blade-lock, stats in Str/Dex/Con can make you a good 4e Battlemind.
If not, 4e invoker can be replicated with with a Cha/Wis build, Moderately Armored + Magic Initiate: Thaumaturgy, Guidance, Bless with a spell emphasis on curse and radiant attack.
That is cool stuff too. And in fairness I like concept a lot...but I do not ignore the numbers. Note my example above...I don't have to be the best, but I can't stomach ineffectual. I want to be a hero of some sort afterall!