That said, I thought the concept of city spirits could be expanded to other classes, and thus was born the idea for the Path of the Streets -- a barbarian possessed by a local neighborhood spirit whose mood and powers change based on how the community thrives.
As always, first drafts, no playtest, yadda yadda constructive criticism et cetera.
Path of the Streets
The streets of dense urban centers can, after years of powerful emotions from the residents, develop their own spiritual guardians. Only dimly-sentient, the spirit tends to reflect the prevailing attitudes of the district in which they dwell. A harbor-side warehouse district, forever slick with the blood of victims of the mob that controls it, may shelter a violent and hateful street spirit. Conversely, a poor but honest inner city neighborhood whose residents make the best of their circumstances and support the virtues of community, education, and brotherhood can spawn benevolent street guardians.
Barbarians, as people with an already powerful emotion that gives them supernatural strength, are magnets for these spirits. Those who follow the Path of the Streets are conduits for their respective spirit. When you select this path, choose a community or neighborhood in an urban or suburban environment; this location becomes the source and home of your possessing spirit.
Righteous Force / Wrathful Brute
When you join the Path of the Streets at 3rd level, the spiritual possession is nascent and shows itself in subtle ways. You might not even realize the spirit is present within them at first. The exact nature of the spirit is contingent on the state of the neighborhood in question, and a spirit can be redeemed or corrupted based on actions within the community. Your Dungeon Master determines the state of your street spirit at a given point in time.
Repeatedly funding, encouraging, and participating in community revival projects make the spirit benevolent. In these cases, you may use Righteous Force while raging, giving allies advantage to attack any enemy you successfully strike in melee until the end of your next turn.
Fomenting fear, intimidating residents, or encouraging the abuse of a neighborhood's resources or community will turn the spirit violent and hateful. When this is the case, you instead become a Wrathful Brute, dealing psychic damage equal to your Strength modifier to enemies adjacent to creatures you strike in melee.
Pillar of the Community
Also at 3rd level, when you join this path, you are recognized as a local resident of import within your spirit's neighborhood. You have advantage on Charisma ability checks when dealing with community residents, and can always find a safe house for you and a number of allies equal to your Strength modifier. Locals will be positively inclined toward you, though whether this is out of genuine appreciation or fear is contingent upon the state of the spirit and community itself.
One with the Streets
Upon reaching 6th level, the spirit's possession becomes more overt, granting a preternatural sense of urban or suburban environments, defined as anywhere with paved streets and at least one building of four or more stories.
You may spend 1 minute in contemplation while standing or sitting on pavement and allow the spirit within you to attune to the area, making it a sort of home away from home. For the next 8 hours, you gain advantage on Insight, Intimidate, Investigate, Persuasion, Perception, and Survival checks made in the neighborhood, and can use an action to disguise self at any time.
At 10th level, you may directly call upon the spirit of the streets to aid you in battle. You may use a bonus action to cause a structure or local feature within 10 feet of you, such as a wall, street, stack of cinder blocks, exposed pipe, or even an overgrown community garden to spring to life and assail a target you can see within 30 feet.
You may elect to use this aid offensively, gaining advantage on attacks against the targeted foe, or use it defensively, causing any attacks against you from that opponent to suffer disadvantage. This effect lasts until the end of your next turn.
When you reach 14th level, the spirit of the streets within you allows you to perform feats of incredible strength. For the purposes of lifting, carrying, or throwing objects, you are treated as though you were Gargantuan (thus, a barbarian with a Strength of 20 can carry 2400 pounds, and push, drag, or lift 4800 pounds). You deal triple damage to artificial obstacles and structures, such as barricades, walls, and doors.
You may also pick up and throw objects or creatures as heavy as 4000 pounds -- about the weight of an average sedan -- with a range of 30 feet. Such attacks are made with disadvantage, but inflict crushing damage equal to 1d6 for every 200 pounds the object weighs. Medium or larger objects will leave difficult terrain in its wake.