Warlocks = evil?

[TarionzCousin]

My current planned solution is to house-rule the warlock so that it can make pacts with celestials or other good-aligned entities or forces (such as the Silver Flame in Eberron).

But the Silver Flame is EVIL!

I'm toying with the idea of warlocks who have made pacts with good entities still retaining a somewhat darker aspect by embodying the less forgiving elements of good such as wrath and justice.

That's a nice touch. Perhaps the very idea of entering into pacts with good entities is somewhat "dark." After all, the good entities don't really have a chance to refuse, do they?