My players' characters are level 5 and about to catch up with Chapter 6 of Hoard of the Dragon Queen and start gaining levels again. Their party consists of
- a Forest Gnome Rogue Assassin with Talon*
- a Variant Human Life Cleric with no magical items currently as she came in a few chapter in to Tyranny of Dragons and after Lost Mines was already completed.
- a Goliath Bear Totem Barbarian with Hew†
- a Rock Gnome Divination Wizard with a staff of defense, spider staff, and wand of magic missiles
- a Variant Human Vengeance Paladin, the de facto leader of the group and the focus of my concern Stats: Str 18, Dex 12, Con 14, Int 10, Wis 10, Cha 16 (Found a Manual of Leadership during a session in between Lost Mines of Phandelver and the start of Tyranny of Dragons)
The Paladin has the Dragonguard Armor and the greatsword Lightbringer,‡ the Great Weapon Master feat, and the complementary fighting style. With the −5 to hit and +10 damage attack hitting most foes consistently at this level, and the ability to bonus action attack if any of his 2 attacks from Extra Attack kill something, he is a seemingly unstoppable force on the battlefield who is consistently pushing out far more damage even when not in Nova mode (Divine Smite) than the Rogue (whose job is high damage) and the Barbarian.
He will soon be considering some Warlock levels, which makes me concerned about his power spike even more.
My question, given the presented information: Will this Paladin always be the character with the highest AC and consistent damage output, or will they start to even out and feel more balanced as a group?
My players are starting to feel... slighted... but they have all played by Adventure League rules and done nothing outside the scope of the published Adventures they are running. I want them to feel fairly treated.
*†‡ Spoilers for magic items from published adventures:
* Talon is a +1 longsword with the Finesse weapon property that deals extra damage to beasts, found in the Lost Mine of Phandelver Adventure.
† Hew is a +1 Battleaxe that deals maximum damage to plant creatures, found in the Lost Mine of Phandelver Adventure.
‡ Lightbringer is a +1 Mace (That I mistakenly made a Greatsword because absolutely no one could use the 'meant for the pre made adventure cleric' item as is so bares some altering) that deals extra damage to undead and the Dragonguard is a +1 Breastplate that grants Advantage on saving throws against the Breath attacks of Dragons, both found in the Lost Mine of Phandelver adventure