Acolyte
Some features state Wisdom modifier instead of spellcasting ability modifier, which excludes the choice of Charisma as your spellcasting ability. Eg. Smite the Faithless.

Armor of Faith: This is similar to the Monk, and suits Avenger as written, but Cleric and Paladin use shields. This features has a max AC 22, is that intended? If not, maybe “While you are not wearing any armor, your AC equals 13 + your Dexterity modifier or your acolyte spellcasting ability modifier”. Plate is still higher until you can max out either of those stats.

Knowledge Domain(Knowledge of the Ages): “As an action, you choose one language or skill. For 24 hours, you learn the language or have proficiency with the chosen skill.” Do you gain a proficiency in a new skill with each use on top of previous ones, or if you use this again does it change the proficiency? If you are already proficient, should it grant expertise?

Knowledge Domain(Divine Insight): This has great benefits, but lasts 8hrs(as Foresight spell) compared to all other domains whose duration is 1 minute. Not sure if it’s an issue, just seemed odd.

Protection Domain(Sacred Weapon): “As an action, you can imbue one weapon that you are holding with positive energy. For 1 minute, you add your spellcasting ability modifier (minimum of 1) to attack rolls made with that weapon.” Is this on top of the normal ability modifier, or in place of it?

Read Thoughts(Knowledge domain): Read thoughts RAW grants an initial saving throw(success blocks further attempts), and then Suggestion without a save. It’s replacement, Detect Thoughts, has no initial saving throw on the mindreading, only the probe, and therefore no chance to avoid the Suggestion. Most Channel Divinity effects are worth 2 mana, and this is already 4 mana of spells(plus the no saving throw). It’s not really a niche ability either, it has great use potential, so it seems unbalanced. Possible solution, “You can cast Detect Thoughts, without expending energy. You can augment it further by expending energy.” The flavour is close, with your version of Detect Thoughts having an augment that gives something along those lines. It keeps in more in like with the power of other Channel Divinity options.

Tempest domain(Thunder Lord): Should the damage from lightning/thunder spells increase by 1d8 vs 1 target for the Cleric, like attacks do for the Paladin and Avenger?

Trickery domain(Cloak of Shadows): Would it be more consistent as “You can cast Invisibility(Illusion) augmented to Continued Invisibility, without expending energy.”, to bring it up to other 2 mana Channel Divinity options, or is the fact it doesn’t require concentration a big enough benefit?

Warrior
Danger Sense: Doesn’t this make you better at Reflex saves than you are with Fortitude at lower levels, if that’s even an issue?

Does Remarkable Athlete and Jack of All Trades(Skald) stack to basically provide full proficiency to the affected skills?

Dervish(Battle Dance)
1. “When you take the Attack action on your turn, you can make one additional attack as part of that action.”
Was wondering what the mechanical goal with the wording was, as the flavour seems to allow a lot of odd options, like “dancing” with a greatsword or heavy crossbow. I can see this style being used with two weapons, single one-handed weapons, polearms(Oberon Martell from GoT), or even a bow(Legolas from LotR), but weapons like a maul you don’t really “dance” with imo.
2. “At 11th level, you can make another additional attack as part of the Attack action as long as you don’t use two hands to make an attack with a weapon this turn.”
I understand locking out d12 weapons, but it also locks out versatile weapons, bows and polearms, is the d10 the balance issue? It still seems to allow two weapon fighting and dueling styles, which pushes the damage up around d10 anyway. Wasn't sure if it mechanics or flavour was the issue.
3. Should the AC bonuses stack from Dueling Master(also requires Shield perk) or Dual Wielder perk? Those feats assume a style where you already can’t use a shield, maybe allowing a higher AC than intended.

Mage
Arcane Strike(Magus): Does this need to specify a main hand attack? If a Magus is using dueling style wielding a longsword, it can draw a dagger as a free action just to sacrifice it’s attack for Arcane Strike.