Movement based barbarian balancing

I made a movement based barbarian subclass but I don't know a lot about balancing as i'm still new at making subclasses. I'll post a screenshot of the features, just let me know anything that should be changed to make the subclass more in line with official subclasses.

Ok i don't know how to post images so I'm just going to copy and paste the text.

Momentum

Starting when you choose this path at 3rd level, when you enter your rage, you can use speed itself to deal damage. Until the rage ends, you gain 20 feet of movement and cannot be attacked with attacks of opportunity. If you move 10 or more feet in a straight line on your turn, you can make an attack roll against every creature in the path of your movement, dealing 1d10 + your Strength modifier bludgeoning damage on a hit. The damaged creatures can only take this damage once per turn, but you are able to keep your momentum if you turn, as long as you have at least 10 feet of movement left. 

Uninhibited Movement

Beginning at 6th level, you have freedom of movement and cannot be attacked with attacks of opportunity while raging.

Brutal Charge

Beginning at 10th level, you can use your action to fortify your body for extra damage in your charge. When you hit a creature with your charge attack, they will take an extra 2d8 thunder damage and must succeed a Dexterity saving throw or fall prone. The DC for the saving throw is equal to 8 + your Strength modifier + your proficiency bonus.

Unstoppable Force

Starting at 14th level, your reaction time has become heightened. While you are raging, if you are about to take damage from a creature within 10 feet of you, you can use your reaction to counter the attack. You reduce the amount of damage taken by an amount of d6s equal to half your barbarian level, and you can immediately make a charge attack against the attacker.