Channel Divinity is just a name. God grant power through worship, Patrons as a "deal" (which really is just a type of deal that clerics make: worship).
This is the single worst aspect of the 5e warlock class design, a the biggest culprit in making the class not feel like the concept. It should be absolutely clear that the patron is not giving you the hex spell when you cast it, you gave or promised soemthing and they gave you the means to take the power you needed and do whatever the hell you want with it.
The fact that people seem to see warlocks as more subject to their patrons will than clerics to their gods is an egregious absurdity.
The invocations last until you rest, and you can change them making them more versatile.
Great, also not relevant to whether the subclass makes a character feel like a warlock, and certainly does nothing to address how much more powerful this is than other cleric subclasses.
Which is a weakness. It makes it so that the base class defines the character vastly more than the subclass, meaning you’re just playing a cleric.
If it being just fluff doesn’t matter, why even make a subclass for it? Just play any cleric and change the fluff.
Which is something they always should have had. It could have been their "thing" but since they made an entire new class for it...
Great, why call it a sorcerer? What’s it got to do with the actual themes and premise of the sorcerer?
And how is it any more "wildly overpowered" than what sorcerers already do?
It’s on top of what the wizard does. It’s a class and a half. The sorcerer isn’t exactly broken as written, but they are a strong class, and you’ve added half of their power to an already equally powerful or more powerful class.