So now it's confirmed that we're getting oath of vengeance paladins, I think it's worth discussing in more specificity what that means for paladins. The oath of vengeance is really intended for Lawful Neutral characters, or more harsh iterations of lawful good. Their tenets are as follows:
Fight the Greater Evil. Faced with a choice of fighting
my sworn foes or combating a Iesser evil, I choose the
greater evil.
No Mercy for the Wicked. Ordinary foes might win
my mercy, but my sworn enemies do not.
By Any Means Necessary. My qualms can't get in the
way of exterminating my foes.
Restitution. If my foes wreak ruin on the world, it is
becacuse I failed to stop them. I must help those harmed
by their misdeeds.

Those are very firm tenets with a clear idea. They are meant to be rutheless, but only to a point. They aren't forbidden from give mercy at all, only to their "sworn foes" whatever that means. Clearly there's an idea that they swear their vengeance against a particular sort of enemy and outside that, there's wiggle room. And importantly, their final tenet makes it explicit that these paladins have a duty to help those harmed by their foes in particular. They take on a real sense of responsibility.

How do we think Larian will handle this oath? Assuming they're able to iron out the kinks in the oath system, how well can they pull off this oath in the best of circumstances? I think it's worryingly possible, even likely that Larian will lean too far into the edginess of the class (which in their defence, that edginess is absolutely present in the subclass by design) and miss out on the nuance of it. I think that if we're just blanket not allowed to show mercy, that would do a disservice to the class and force it into a villanous role it's not meant for. It's a class that accepts some enemies as deserving mercy. Not even just some people, but some enemies against you. How Larian interprets that will really make or break the class.