Fluff

Witches are wielders of magic many find strange and uncomfortable. While magic alone can be unsettling and confusing for many, witchcraft is often even more so. As such, it is not uncommon for witches to become ostracised and vilified even by other magic wielders. Witchcraft can appear to violate the laws of magic itself. What many of these do not realise is that, in many worlds, witchcraft is far older that many other forms of magic, it does not violate the rules so much as predate them. Regardless of their reputation, the interests and motivations of witches can be as varied as any practicioner of craft. 

Much of witchcraft can be seen as the control and understading of life, in its many forms. Whether producing potions to preserve or end life, manipulating the minds of livng beings, or invoking the power of spirits who have long since abandoned physical form, witches make formidible allies as well as foes.

Subclasses (Covens)

• Coven of Brewers

  • Makes potions and poisons
• Coven of Familiars/Beasts

  • Stronger familiar with statblock that scales with PB and has a few forms focused on combat, scouting or other utilities
• Coven of Hexers

  • Hex/Curse based features, like hexblade but caster based
• Coven of Seers

  • Prophecy based features
  • Spells like augry, divination etc.
  • Discouraging Warning. Starting at xth level, you can use an action to choose a creature you can see within 30ft and show them visions of a terrible fate that may await them if they follow a particular course of action. WIP. The creature must make a Wisdom saving throw against your witch spell save DC or be unable to willingly perform the action you described within the next minute. At the end of each of its turns, the creature can attempt the saving throw again, removing the effect of this feature on a success. (Prof per LR, or just make it unlimited)
• Coven of Ritualists

  • Maybe can cast ritual spells from any list
• Coven of Skies

  • Broom based features
• Coven of Claws/Transmuters/Monsters

  • Transforms self for martial bonuses
  • Gets primal savagery and several ways to improve it (like warlocks with eldritch blast). 
  • Maybe features are focused on natural weapons/unarmed strikes so stuff like alter self is stronger
• Coven of Spirits/Mediums

  • Necromancy/fear based caster that controls spirits
• Coven of Blooddrinkers/Bloodletters

  • Blood magic based damage caster
  • Can damage self or willing/incapacitated creature to enhance spells.
  • could also just be "dark magic" flavoured and injures self to enhance magic
• Coven of Secrets

  • Maybe gets spells from other lists
  • Probably gets a book of secrets (necronomicon/darkhold style)
• Coven of Elements/Primordial

  • Elemental themed (beyond the main 4, includes ice)
• Coven of Night

  • Stelth/darkness based

• Coven of Horrors

  • Fear based

• Coven of Warriors

  • Martial based, granting weapon/armour proficiences and self-healing/resistance 

Discarded Features

kept here in case I want to reuse them

Spirit of Focus. When you make a Constitution saving throw to maintain concentration on a witch spell or cantrip, you can use a reaction to gain advantage on the roll.

Spirit of Focus (Alt). When you cast a witch spell or cantrip that requires concentration, you can choose to have your spirit to focus on the spell instead. This spell does not require concentration for this casting and lasts for its full duration. The spell ends early if you choose to end it (no action required) or if you are incapacitated. Once you use this feature, you cannot do so again until you finish a short or long rest and the spell has ended.

Spirit of Focus (Alt2). When you cast a witch spell or cantrip that requires concentration, you can choose to have the spirit to aid you in focusing on the spell. You concentrate on the spell as normal, but casting another spell that requires concentration does not end this spell. If you are concentrating on two spells and are forced to make a saving throw to maintain concentration, you make one saving throw for both spells, ending both on a fail. Once you use this feature you cannot do so again until you finish a short rest or long rest without currently concentrating on spells.

Witch's Flight

Starting at 10th level, you can use a bonus action to grant yourself a flying speed equal to your walking speed for 10 minutes. If you already have a flying speed that is equal or greater than your walking speed, your flying speed increases by 10ft.

Once you use this feature, you cannot do so again until you finish a short or long rest.

This is arguably already handled by the Fly spell

Enchanted Runner

Optional Feature that replaces Enchanted Transport

Starting at 10th level, you can use a bonus action to enchant a non-magical object that is no more than 10ft in any dimension, such as a broom, a cauldron or a rug. The object becomes magical and sprouts legs. Once on each of your turns for the next hour, you can command the object to move up to 50ft (no action required). The object can climb difficult surfaces, including upside down on ceilings, without needing to make an ability check. A creature can grasp or mount the object to be moved with it.

At the end of the duration, the magic effect ends and the object becomes non-magical again, falling to the ground if the only thing holding it aloft is this effect. The effect also ends early if the object is ever more than 1 mile from you, if it is ever carrying more than 500 pounds or if the dispel magic spell is cast on it.

Once you use this feature, you cannot do so again until you finish a short or long rest.

Invoke Spirits (WIP)

Starting at 3rd level, you can draw power from magical spirits that surround you, imperceptible to most mortals. This power is represented by your Spirit Dice, which are d4s. You have a number of these dice equal to your witch level, and you regain all expended spirit dice when you finish a long rest.

When you reach certain levels in this class, the size of your Spirit Dice increases: at 5th level (d6), 11th level (d8), and 17th level (d10).

Once per turn, you can use your Spirit Dice with the features below.

• Spiritual Deceit. When you force a creature to make a Wisdom saving throw against a witch spell you cast, you can expend one spirit die, roll it, and subtract the result from the creature's saving throw. Too strong?

• Spiritual Focus. When you make a Constitution saving throw to maintain concentration on a spell, you can expend one spirit die, roll it, and add the result of the roll to the saving throw.

• Spiritual Soothing. When you restore hit points to a creature with a witch spell, you can expend one spirit die, roll it, and add the result of the roll to the healing that creature receives from the spell.

• Spiritual Wrath. When you damage a creature with a witch spell or cantrip, you can expend one spirit die, roll it, and add the result of the roll to the damage that creature takes from the spell.

This is feeling more like a subclass feature. However the idea of witches drawing magic from spirits could be a class defining thing, just need to find a suitable mechanic that fits.
Also a little too close to sorc's metamagic I fear

Maybe choose a spirit to call upon at the end of a LR (e.g. one spirit will increase spell damage, another will increase healing, another will improve spell save etc.)