Ranger

Beast Master

Source: Player's Handbook

Says what it is on the tin. You area ranger with a cool animal companion, your choice from a variety of pretty standard creatures or a magical primal creature which is alot cooler and overall better mechanics.
The Features you get are pretty underwhelming if i really wanted to play this kind of of class i would suggest going with the Beastheart instead.
BUT if your restricted to content i would defiantly work with the player to provide some much needed buffs and more interesting mechanics to this subclass. Maybe some coordinated attacks or some unique magic items and give some options for scouting and tracking with your companion as well as being able to mount them for travel or combat AND some cooler more powerful options for your companion .

2024 Revision Available

The revision basically just streamlined the options, no more animals only primal beasts. still has the same issues and i would still have the same edits to make it cooler.

Coven

Source: Hexbound, Pg 30

A cool subclass that's kinda like they took the primal beasts from beast master then built all the mechanics around it. you choose one of three nature gods/spirits/patrons whatever the setting your playing in helps with, the elk is all about magic boons, the snake is defensive and the wolf is for meele attackers. the boons they grant as features are pretty good although i think i would make the snakes defensive boons more active than requiring you to be under certain levels of HP. if you were looking for a Ranger who is REALLY in touch with the spirit of nature this is the subclass to run.

Drake Warden

Source: Fizban's Treasury of Dragons

Is like beast master but better cause its a Dragon. the features are more themed and on brand but you are restricted to a dragon *Gasp*. i think the subclass is pretty solid but as a DM i would allow flight much earlier than level 15 like common?! 7th level when the dragon gets wings would be when i would recommend but when some Races can get innate flying speed?!?! whats the point just give your player flying speed! don't be scared. aside from that i would work with the player to get some some magic items to bolster this subclass further.

Fey Wanderer

Source: Tasha's Cauldron of Everything

An overall solid class for the ranger wannting a Feywild twist, perhaps a character who is from the feywild or one who was stolen away by meddling fey. it has some good offensive features, some good non-combat features and some cool themed spells. i would allow dreadful strikes t proc on all attacks not just once per turn and i think Fey reinforcments could be altered more so its not just a free spell cast but something more eventful and fantastic, perhaps a unique fey tied to the ranger's story. it also has some cool physical effects for your character and i am a fan of those.

2024 Revision Available

I honestly don't think they changed anything, just the wording, which is fine cause it was a cool class to begin with.

Field Researcher

Source: Floral Dragon Sub-Classes, Pg 4

Overall pretty solid class, has some simlar beast to Fey wanderer but more on Intelligence skills than wisdom. Gives you an extra attack as a bonus action and has the HUGE boon to give allies advantage on attacks or checks as a reaction. while in combat this is fantastic, allowing rouges to get sneak attack. giving heavy hitters better odds while still having your entier turn to yourself this is massive for non-combat basically giving anyone advantage on any check they make so long as your within 5ft. i would restrict this to only work on skills you have in common with the other player otherwise you might as well call this subclass the 'Advantage Battery' or perhaps put a limit on its uses to be the same as proficiency bonus or even half that.
You also get some cool stuff relating to plant and animal summoning. this is very much a support tunned subclass but what a support it is.

Gloom Stalker

Source: Xanathar's Guide to Everything

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2024 Revision Available

Horizon Walker

Source: Xanathar's Guide to Everything

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Hunter

Player's Handbook

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2024 Revision Available

Monster Slayer

Source: Xanathar's Guide to Everything

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Swarm Keeper

Source: Tasha's Cauldron of Everything

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Urban

Source: Guide to Drakenhime, Pg 167

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