I mean imagine if the Ranger had a feature called "Monster Hunter". By spending your bonus action, you can deal, say, 1d4 additional damage* on all your attacks, and it scales by d4 every 2 levels after the first. Then you have a second feature, "Favored Enemy", that lets you pick a type of creature that you've really trained against, and when damaging these creatures, you deal your Monster Hunter damage without needing to spend a bonus action.
*I'd like to make this force damage to bypass resistance to non-magical weapons, but I know there are people who would wonder exactly how the Ranger is dealing "magical" damage, lol.
Wouldn't that be a better way to give the Ranger bonus damage, reinforce his role, and make Favored Enemy a bonus, instead of making the feature simply unreliable?
This is probably not the thread to suggest changes to the class, but it took me like five minutes to find something better than Hunter's Mark for the Ranger, lol.
I'm sure someone will tell me how horribly unbalanced that is and how it would turn Rangers into damage gods.