I'm splitting this off from the Tasha's thread so as not to clutter that one up. Reading that thread, and discovering what Wizard's is replacing Favored Enemy with in Tasha's, has really made me realize just how clunky the ranger is implemented. They're the only class that gets a unique spell to increase their weapon damage, instead of a class feature. Which has really made me realize that perhaps the best way to deal with it is to just replaced favored enemy AND hunter's mark.
I think one of the problems with the Ranger being under powered is that they have a spell that should be a class feature. And since I can totally house rule things in my game, up to and including removing spells from spell lists, this seems like a good way to fix things.
TL;DR - I think the best way to help the ranger is to remove hunter's mark and make it a class feature instead. See Hunter's Eye below.
Look at the other classes and how they get damage increases. Rogues get sneak attack, barbarian's have rage, monks get extra bonus action attacks, paladins get smites (eventually auto smites), and fighters get more attacks and action surge.
To me, the Paladin and Rogue are all about big damage spikes, with the paladin trading off toughness for less consistent and more spiky damage (at least until higher levels). They are the two classes that get to drop one big damage attack a turn (or multiples, if the paladin goes nova). The Fighter and Monk are just about getting more attacks to add damage that way, trading off big spike damage for a more consistent damage output. Which then gives us the Barbarian and Ranger, who are more about adding small amounts of damage to fewer attacks, which is another method of steady damage. In this model, the barbarian is like the paladin, trading off less damage for more protection (the damage reduction), while the ranger gets slightly more damage for less toughness.
In short, Rogues and Paladins spike damage, Monks and Fighters are the most 'consistent' damage dealers, thanks to more chances to hit and deal damage, and Barbarians and Rangers are the middle road: smaller damage bonuses over a few attacks.
Which brings me to the ranger, and it's unique problem. Because their extra damage is tied up in a spell, they have two problems to contend with: their extra damage takes a bonus action to activate (like the barbarian), but it also requires concentration and a precious spell pick. Which means they can lose their extra damage (which I believe is assumed to basically be 'always on') to a bad roll. And unlike the paladin, their extra damage cuts off simultaneous access to some pretty cool spells for all of the archetypes.
I mean we're all in agreement that the power of super racism is just shitty on top of things. But the term favored enemy doesn't need to mean a category of creatures: it can also just mean that you've favored one creature as your 'prey.' In short, lean into the hunter aspect and treat favored enemy as a hunter's focusing in on their prey.
Which is why I've been tinkering with this replacement class feature so much. I've done a lot of revisions, but I think the one below is really solid. And while WotC can't do something like this, as it would basically errata a spell out of existence, there's nothing saying that you can't do that at your home table, with a much smaller audience.
Hunter's Eye
1st-level ranger feature (replaces Favored Enemy and hunter’s mark)
Calling upon your bond with nature, you can mark a foe as your quarry. You can use a bonus action to mark one creature that you can see as your favored enemy until you take another bonus action to dismiss your mark or mark a different creature as your favored enemy.
You have advantage on any Wisdom (Perception) or Wisdom (Survival) checks made to find or track your favored enemy. When you hit your favored enemy with a weapon attack, you deal an extra 1d4 points of damage.
At 6th level, you can mark a creature as your favored enemy when you roll initiative, and the extra damage increases to 1d6.
At 14th level, when you reduce your favored enemy to 0 hit points, you can use your reaction to mark another creature as your favored enemy, and the extra damage increases to 1d8.
Yes, I basically just made hunter's mark a class feature (as it should have been, IMO). But it has a few notable differences. First of all, by removing the spell this both opens up a spell pick and removes the concentration requirement. Now a Beastmaster can actually make good use of Beast Bond. Hunters can actually use the various ranger smite spells. With the hunter's mark bottleneck gone, you'll get more variety in your rangers.
Secondly, by making this a class feature it allows you to scale both effects and damage much more easily. You start with a d4 and a bonus action, which makes ranger less attractive for a dip and gives you somewhere to go. But at 6th level you get both a damage scaling and the ability to pick a favored enemy when you roll initiative. This starts freeing up bonus actions for two weapon fighting, beast attacks, and stuff like shield mastery. And at 14th level, just a few levels after the paladin, you remove the bonus action entirely and up the damage to 1d8, matching the paladin.
With the addition of sharpshooter, two weapon fighting, or a beast I feel like the average damage of the ranger finally sits about where the other classes are at, especially the paladin.
I'd love some feedback on this before I implement it live for my house rules.