Fixed Path of the Berserker

The main deviation from the subclass as written is giving the player more to do during the Frenzy rage. I removed the option to make the rage frenzy or not, instead, barbarians always enter frenzied rage. In exchange, the barbarian treats all weapons as though they have the thrown weapon property (20/60 ft.) and can make their bonus action attack with such a weapon. At level 6, they gain the ability to throw creatures that are Large or smaller. I changed the Intimidating Presence saving throw to scale with Strength instead of Charisma. The Retaliation attack at level 14 no longer requires a reaction to use, but instead can be made a number of times equal to the barbarian's proficiency bonus.

With these changes, I really think the Berserker Barbarian has a lot more options, putting it on par with the other subclasses. The player should now feel like they can really use their rage features to their advantage, entering rage early and launching their weapons at their foes before running in to pick it up and start swinging. Once their in the thick of battle, they can begin to throw their foes around like ragdolls and draw the attention of their enemies, becoming the true aggro for the party. Of course, drawing attention means they get to return several brutal attacks to their victims before their next turn even starts.

Frenzy

Starting when you choose this path at 3rd level, you go into a frenzy when you rage. Your fury is so great that all weapons are treated as having the thrown (20/60ft) property, in addition, you gain proficiency with [Tooltip Not Found] weapons. For the duration of your rage you can make a single weapon attack as a bonus action on each of your turns after this one. When your rage ends, you suffer one level of exhaustion.

Mindless Rage

Beginning at 6th level, you can’t be charmed or frightened while raging. If you are charmed or frightened when you enter your rage, the effect is suspended for the duration of the rage. Also, when you make your bonus action frenzied attack, you can choose to throw a creature within reach instead. The creature must be Large or smaller and must make a Strength saving throw, DC = 8 + your proficiency bonus + your Strength modifier. The creature can be thrown a distance of 10 feet. If it collides with another creature, both take 2d6 bludgeoning damage. This damage increases to 2d8 at 9th level, 2d10 at 13th level, and 2d12 at 17th level. This feature can be used a number of times equal to your proficiency bonus per rage.

Intimidating Presence

Beginning at 10th level, you can use your action to frighten someone with your menacing presence. When you do so, choose one creature that you can see within 30 feet of you. If the creature can see or hear you, it must succeed on a Wisdom saving throw (DC equal to 8 + your proficiency bonus + your Strength modifier) or be frightened of you until the end of your next turn. On subsequent turns, you can use your action to extend the duration of this effect on the frightened creature until the end of your next turn. This effect ends if the creature ends its turn out of line of sight or more than 60 feet away from you.

If the creature succeeds on its saving throw, you can’t use this feature on that creature again for 24 hours.

Retaliation

Starting at 14th level, when you take damage from a creature that is within 5 feet of you, you make a melee weapon attack against that creature. You can use this feature a number of times per rage equal to your Proficiency Bonus.