Rolling a new character.

[KorvinStarmast]

Since you are at level 10, I'd suggest that you go all Paladin.

Your aura adds your Cha saving throw bonus to everyone.
I'd make the CHA 16 or 18.
Your aura makes anyone in it immune to being frightened.

Agree with Resilient Con. When you do cast a spell having proficiency in CON saves helps. Paladin has a number of spells that require concentration.

Your wizard and cleric have plenty of divine and arcane magic.

Your lay on hands will allow for healing when necessary.

Sometimes, divine smiting is a great way to help take down the enemy.

Which Oath? All are good.

The nice thing about Watchers is that at level 7 you just boosted everyone's initiative (within your aura radius) roll by your Proficiency bonus. We discovered that this was very handy. At present your bonus is 4. (level 10).

Watcher's Will, a Channel Divinity feature, allows you once per SR to give you allies advantage on INT, WIS, and CHA saves. As you go up in level those saves sure crop up a lot. We found it to be handy.
Abjure the Extraplanar: I used this quite a bit to break up crowds of demons we fought in later Tier 2 and Tier 3.

The bonus spells for Watchers are decent. You end up always having detect magic available, which frees the cleric and wizard from having to prepare it. The usefulness of that crops up every so often.

Next level (11): your melee attacks add 1d8 radiant damage whenever they hit, regardless of whether or not you use divine smite.

The barbarian could use a battle buddy. I'd suggest you fill that role.

Have fun, in any case.

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Aside: if you go Lore Bard, go pure bard. You don't need to be trying to pile damage on with your cantrips; at level 10 you'll have 4 total magical secrets. If you are intent on adding a better damage cantrip, easy to grab one with one of your magical secrets.

Still agree on your Res Con feat. Bard buff and debuff spells are often concentration.

Note: max Charisma. Spell DC is goodness. I discovered that up casting Blindness/Deafness (level 2 spell) began to have a larger success rate at higher levels and it would debuff more enemies. The blinded ones are attacked with advantage by your allies.

Wall of Force is a good spell to get with level 10 Magical Secrets, but there are so many good ones ... Telekinesis is pretty good as well.

Counterspell.

Cutting Words is good all game long to reduce enemy attack rolls or reduce damage.