It'd be rather amusing to play an Arcane class without a SP bar... that is, all the Warlock's abilities are Spell-like abilities, and thus doesn't require spell points. Think about this. This is no regular caster class.
I think it could work pretty good with the current system if implemented right.
For those saying it would be a weak class, I have to disagree. Keep in mind that, in PnP, Sorcerers and Favored Souls are also pretty weak, but due to the nature of DDO they work well enough. Only problem I think it'd need to be adressed is damage (9d6, which is the highest damage the Eldritch Blast can achieve, is not that big of a deal), but that could easily be fixed with enhancements and items that give/improve crit range/multiplier.
The eldritch blast modifications would work like the metamagic feats, where you simply activate or deactivate to create various shapes and effects to the ray attack.
That being said though, I think it's rather unlikely that we'll see this class being implemented.