Warlocks: Are they incredibly broken, and can they be fixed?

[lsfreak]

Less utility than any primary caster (especially other arcane casters). Significantly less damage output than an ubercharger, a ToB character, or even a well-built rogue. They can fill multiple roles in the party - party face, archer, arcanist, itemcrafter - but can't fill any of those but maybe itemcrafter (when artificer is banned) as well as another character.

So no, they're not broken. If anything, they're a little on the weak side as-is, fit well for dipping 1 or 4 levels but not really all that great all the way through. I'd up the number of invocations they know and homebrew some more interesting invocations in order to make them a bit more powerful.