Barbarians are really well balanced, mechanically interesting, and fun IMHO, with one issue. There's no class-specific customization! Consider every other class:
- Cleric: Your deity outlines Channel Divinity, cantrips, domain spells, and a Disciple power.
- Druid: Circle of Oak or Circle of the Moon lets you go more caster-focused or Wild Shape focused.
- Fighter: Death Dealer, Superior Defense, Unerring Attacker, Multiattack, and Unstoppable all give ways to customize your fighter.
- Monk: Your Monastic Tradition determines which Ki Abilities you have.
- Your Oath gives you Channel Divinity options and spells, and your Mount differs from other paladins
- Ranger: Your favored enemy gives you special training variations at levels 1, 1, 2, and 8.
- Rogue: Your rogue scheme gives you a Sneak Attack style, Skills, specific feats, and a skill trick. Later you choose a Multiattack option
- Wizard: For all that I'm bitching all over da forums about how weak Tradition of Wizardry is, it's still a thing you choose that means you're one style of wizard and others are a different style of wizard.
Shouldn't Barbarians have some features where they choose X option instead of Y option? I'd set it up to be something in one of thse categories. A lot of it can be insta-fixed by 1. Taking an existing feature that's obviously one of these categories, and 2. making it an option instead, with options more aligned to the other categories
- Skirmisher/movement/moar attacking
- Pure damage