One of my last 2Ed PCs was a Minotaur F/MU from a charioteering plains tribe, visually based on the picture of the Hurloon Minotaur and playing of Native American legends of the Great White Buffalo.
OK, let me show you what different combos can result in thematically similar but mechanically different characters. Parenthesis indicate subclasses.
This could be a Fighter(Eldritch Knight), a Bard (Valor), Bard(Sword), a Wizard(Bladesinger) or maybe a Warlock(Hexblade).
All would get some armor &martial weapons, the ability to attack at least twice, and spellcasting.
Most can use shields, and Bard/Wizard/Warlock can get 9th level spells.
You could also do Fighter/caster to have access to two subclasses, possibly Fighter(RuneKnight)/Bard(Eloquence) which gives you a small number of elemental powers, a size-based buff, and the ability to rally troops or discourage enemies.
Barbarian(Ancestral Guardian) is an outside possibility as it can summon spirits of the ancestors in combat or use them for Clairvoyance/Augury on top of being buff-murder-person. Thematically appropriate, not sure how it fit the rest of the concept.
It could also be several of the Paladins (Ancients, Vengeance, Glory, etc) as paladins no longer have to be Sir Galahad. We have a party-paladin (Oath of Ancients) who is known for his revels and bachanalias.
Late stage 3.X PCs included:
1) a polearm-wielding githzerai monk who could grow a size class. Mechanically centered on maximizing opportunity attacks, controlling movement on the battlefield. (Also played a human versions of same in a convention game.)
5e keeps the feats of 3e so there are a number of "stand still" feats. You could got for the generic Great Weapon Master/Sentinel or the dedicated Polearm Master. Or layer them up for total comedy.
Fighter(Battlemaster) has a number of "fall down/lose your weapon/I can take an AoO just because/I can let a PC take an AoO/I can boost my attacks/debuff their attack" stunts.
All Monks have stunning blow still. Monk (OpenHand) gets push/knockdown plus a limited "you can't attack me". Monk(Astral Self) gets ghostly arms with extended reach so keep the "bigness" flavor. And it can provide haste-ish effects of bonus AC and extra attacks.
Again in oddball territory, Barbarian(Beast) might work. You can get a tail with reach that can also do a parry and it can cause a target to go feral and use its reaction (AoO) to attack a creature of your choice.
Mix with Monk(Astral) and maybe all the ghost limbs are tails for flavor.
There is an enlarging Barbarian(Path of Giants) in the guide to giants that could also fit and it can go to size Huge and make weapons do elemental damage. Mix with Fighter(Battlemaster) or Monk(...) for flavor.
Hope this provides examples of what the system could do.