Hunter subclass. This was implemented pretty well, from what I can see. I didn't test all the options, but based on the descriptions it looks like they implemented them right. You can either pick the Colossus Slayer and do 1d8 damage to creatures you hit when they don't have max HP, or you can pick Giant Killer and use your reaction to attack a Large or larger creature within 5 feet of you immediately after its attack, provided that you can see the creature. Or you can do Horde Breaker, which allows you to make another attack with the same weapon against a different creature that is within 5 feet of the original target that you attacked. I have tested both Colossus Slayer and Horde Breaker, and both seem to work just fine, so I have no reason to believe that Giant Killer doesn't work as expected.

As for Beastmaster... Sigh. I've said it on another thread, but I'll repeat it here. Animal Companions are not the same as familiars, and we need to have a totally distinct separation between the two. Here are the main differences that we need implemented in the game:

1. Animal Companions are not summoned. You can have an initial spawning outside of combat, indicating that the ranger went out and found an animal and convinced it to be his/her animal companion, but it is not a magical beast that was summoned from another plane of existance. If it dies, that's a real life animal that has died. It isn't a magical animal that you can just unsummon and summon. It is like a comanion in your party. Therefore, if it dies, you should not be able to simply summon another animal right away. There should be some sort of consequence for allowing it to die - like you can't have another animal companion until after you've taken a long rest, no matter when you first spawned the animal. (5e calls for an 8 hour bonding with a friendly animal.) The point is to indicate that time has passed since the loss of a previous companion, and now you are finding a new one. Also, since they are not summoned, they should never be de-spawned. You can maybe dismiss them for good, but they should not de-spawn when you long or short rest. They should remain with you until you dismiss them and they run off into the wilderness.

2. Animal Companions can fight. Unlike Familiars that cannot actually Attack, Animal Companions can obey commands and can run up and attack enemies on their own turn. Now, typically in 5e Tabletop, this requires the Ranger to use an Action to give a command. If they have an appropriate special ability at later levels, this can be turned into a Bonus Action, showing a progressive familiarity with training and commanding beasts. But ultimately in TT it is an Action. However, in TT, the point is that the Ranger can use one Action and command the animal to "Attack that Goblin," and it will spend all of its turns attacking that goblin until it's dead. You don't need to command it each round. That, admittedly, might be difficult to do in a video game. The best way to handle it would be to have Animal Companions be AI controlled. On a Ranger's turn, they could use an Action to Command Animal Companion and then select a target to have it attack, or if the Ranger wants it to change its tactics, he/she could use an Action to do so (such as have the Animal Companion Disengage and retreat, Dodge, Dash, or even Help someone). If the animal's target is dead, it does nothing, waiting for its master to tell it what to do next, or maybe it returns to the master's side until given a new instruction. Each turn, as the TT rules state, it uses the Dodge action until given new orders. This would be a more accurate "benchmark" 5e implementation of Animal Companions.

3. Animal Companions should be able to be named, thus giving them more familiarity to the player. Anything you name creates a connection. Any kind of customization we can give to the animal makes it that much more special. So, I would like to suggest that we have the ability to name them and even change basic coloring or something - anything to make the animal more than just a magical construct that is a meat-shield minion we can throw at enemies and we don't care if it dies.

Right now, Animal Companions are made not as cool because Familiars can do pretty much everything an Animal Companion can do. Both can be spawned at any time, you can attack with either, and you can control either without expending Actions or Bonus Actions or anything. Basically, the main thing that makes the Beastmaster so cool is completely thrown out the window because all Animal Companions are - well, they are nothing but glorified Familiars in BG3. Some Familiars are even BETTER than Animal Companions. So, why even waste your time being a Beastmaster? Just make someone with a Find Familiar spell and you've got something WAY better - especially a Warlock Pact of the Chain familiar. I've played the Beastmaster multiple times, and each time I found myself trying to love it, because it's one of my favorite subclasses, but only feeling like it was pretty much worthless to take that path.