Regarding hunting traps and the like, they definitely fit in the Ranger's wheelhouse. I don't feel like they should
define the class, but it makes sense that the Ranger would be the expert in their use. So I think they should be listed as Tools, and while other classes can use them effectively, the Ranger should have Expertise.
Hunting Traps: From my own limited experience with hunting traps here in the real world, they are something that you spend a few minutes setting up, and then you come back a few hours later and check. If your trap is successful, you find a certain amount of food, or a certain cash amount in resources. (At least, this is how lobster pots work.) They're not battlefield weapons, and they're not necessarily "booby traps" that inflict damage.
So to translate that into D&D terms, it's a tool that you set up and leave over a Long Rest. When you return to check it a few hours later, the DM asks for a Wisdom (Hunting Trap) check to see what he finds in the trap. It could be a certain amount of rations, or a certain GP value of pelts, or what-have-you...hunting traps are used for a variety of reasons. It might also trigger a random encounter, because some horrible forest monster took the bait instead!
Hunting Lures: I'd lump these into the same category as traps. They're similar: you spend a few minutes setting them up, add some bait, and then you back away a hundred paces or so and hide. When your quarry comes up to take the bait, you shoot it. I've only done this a couple of times in real life, so I'm hardly an expert, but it works.
So to translate this into D&D terms, a lure would also be something that you set up and leave, probably over a Short Rest. Perhaps the party is on a quest to catch someone's beloved pet, or they're trying to find out what monster is killing the local cattle? Anyway, the player announces what kind of creature they are trying to lure, and the DM would call for a Wisdom (Hunting Lure) roll to see if the monster shows up. And whether or not it brought friends.
Net: as others have already discussed, this should be a Tool.
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Anyway. I've used these things successfully and easily, and I'm absolutely not a Ranger. (Those of you who are: thank you for your service.) So to address the use of hunting traps and such, I think the Ranger class only needs three adjustments:
Under "Proficiencies," change:
Tools: None. Hunting Traps, Hunting Lures, Net
Under "Class Features," add:
Expertise: At 1st level, your proficiency bonus is doubled for any ability check you make that uses Hunting Traps and Hunting Lures.
At 6th level, your proficiency bonus is doubled for any ability check you make that uses Nature and Survival.
And under "Starting Equipment," add:
- (a) a Hunting Trap or (b) a Hunting Lure