Is this homebrew Music Domain balanced compared to the official domains?

I am making a compendium of homebrew Cleric subclasses, spells and feats, but I want to make sure it is actually balanced and there are no glaring loopholes or broken combos with existing feats, spells, and subclasses before I release it. Is this homebrew Music Domain balanced compared to the other cleric subclasses?

Music Domain

Although usually the realm of bard, musical magic is often used by divine entities. God of music include Apollo, Bragi, Olidammara, and Milil.

Domain Spells

Level
1st Heroism, Alarm
3nd Calm Emotions, Enthrall
5th Beacon of Hope, Tongues
7th Dominate Beast, Conjure Woodland Beings
9th Danse Macabre, Commune (R)

Bonus Proficiencies

You gain proficiency in the performance skill, and in 4 instruments of your choice. Choose one instrument you are proficient in. You double your proficiency bonus for skill checks made that involve playing that instrument.

Song Of Encouragement

Whenever you cast a spell of first level or higher that has a verbal component, choose one creature within 30 feet of you. That creature gets a bonus to one ability check, saving throw, or attack roll they make within the next minute of their choice equal to the level of the spell you cast. If they do not use the bonus within the minute it is lost. If a creature has multiple bonuses, they can only benefit from one on any given use.

Holy Voice

You are unaffected by the silence spell.

Channel Divinity: Musical Number

At second level, when you are not in combat, you can use your channel divinity to perform a 1 minute divinely inspired song and dance routine to convince/intimidate onlookers. For the next 10 minutes, you gain advantage on all charisma checks involving creatures who saw and heard your performance.

Channel Divinity: Enchant Creatures

At 6th level, you can use your channel divinity and perform a one minute song that enchants weak onlookers. At the end of the song, all creatures of CR 1/8 or lower who were within 60 feet of you during your performance must make a wisdom saving throw. Otherwise, they serve you loyally for the next hour, though they will not put themselves in immediate danger, and all enchanted creatures will stop serving you and run away if any of them take damage.

Potent Spellcasting

Starting at 8th level, you add your Wisdom modifier to the damage you deal with any cleric cantrip.

Epic Composition

At level 17, you can spend 10,000 gold and 100 hours to create a musical masterpiece, a scroll of sheet music with immense power. You can do this only once, though you can recreate the same piece for 1,000 gold and 10 hours if the original is destroyed. As an action when you have both hands free, you can unroll the scroll and the sound of the music will begin to play magically all around you for the next minute. You must have both hands free during the entire minute to conduct the magical music. During this minute, you cannot concentrate on spells, make attacks, or cast spells. If you are unconscious, the music ends. At the end of the minute, if the music played for the entire minute an effect occurs depending on the piece you created and the scroll is destroyed:

Also Sprach Zarathustra:
All creatures, excluding yourself, within 120 feet of you take 10d10 radiant damage and are blinded until the end of their next turn. All magical darkness within 120 feet of you is dispelled. This counts as one round of exposure to direct sunlight.

Cannon in D:
You cast meteor storm without expending a spell slot.

Komm Susser Todd:
All creatures within 1 mile of you become telepathically linked. They can read the surface level thoughts and emotional state of any other creature in the linking, regardless of language proficiency, as long as they are in the same plane of existence. This linking lasts for 1 hour, after which, all creatures in the linking, including you, take 6d12 psychic damage. A creature killed by this damage disintegrates into orange goo.

How many uses of bardic music does the Heartfire Fanner get?

The heartfire fanner (Dragon #314) mentions

the heartfire fanner gains the bardic music ability as a 5th-level bard if he did not already have it

[…]

A heartfire fanner’s class levels stack with any bard levels for all bardic music calculations, including the number of uses of bardic music available per day.

How many uses does the Bard 0/Heartfire Fanner 1 get? 1 or 6?

Does playing magical music count as casting a spell?

So in DnD 5e, my bard character happened upon some fragments of a musical composition. When my character tried playing it, it caused some sonic-charged magical effect.

My question is–specifically in the context of conditions like Invisibility where when casting a spell or making an attack drops the Invisibility–does playing this particular piece of music, that happens to have a magical effect, count as casting a spell or making an attack?

Music symbols in Excel software

https://www.google.com/search?q=music+notes+symbols+and+names&prmd=isvn&sxsrf=ALeKk014o9KmAlDHaO3RfEyKUv6IyL2AJw:1598368052273&source=lnms&tbm=isch&sa=X&ved=2ahUKEwi1kuf_0LbrAhXXyTgGHbT8B2UQ_AUoAXoECA4QAQ&cshid=1598368852656&biw=360&bih=592

https://en.wikipedia.org/wiki/List_of_musical_symbols

A Complete Guide to Chord Symbols in Music

https://en.wikipedia.org/wiki/Function_(music)

Can we store music symbols in Excel worksheet ?.

If yes, what will be the data types for storing music symbols in cells?

Can we write functions or formulas for analysing Music symbols stored as Excel data?

Ventriloquism and Bardic Music

Suppose a bard is trying to remain invisible while still inspiring companions. If the bard starts singing, they make themselves a target. If the bard uses Ventriloquism, they can potentially make noise without drawing attention to their actual location. However, this means their allies will be listening to a figment, not the actual bard, so bardic music fails.

What happens if the party makes the save vs ventriloquism? Now, they know the spell voice is fake. Does that mean they hear the real voice? Would they be able to hear the bard singing for real? Or does the ventriloquism spell still block the bard’s actual voice?

From the Ventriloquism spell in the SRD:

With respect to such voices and sounds, anyone who hears the sound and rolls a successful save recognizes it as illusory (but still hears it).

This does not state the original voice could not be heard. Nor does it state that it could. Typically, with spell descriptions, it does not grant anything it does not say it grants, but nowhere does it say the original voice is gone…

From the description of "Saving throws and Illusions (Disbelief)" in the SRD:

A successful saving throw against an illusion reveals it to be false, but a figment or phantasm remains as a translucent outline.

This only discusses visual illusions. It does not mention whether or not the original image is visible when an illusion is defeated.

So, back to my original question: would a party member who made the save against ventriloquism receive the benefit from the Inspire Courage?

Note: I recognize an easier method is using the Message spell, but my group is trying to determine the limits of Ventriloquism and how it interacts with other magic.

Can musical instruments under the effect of Animate Objects be used to make music?

Can Animate Objects be used to make musical instruments produce that instrument’s music?

The spell’s description is a bit vague as to how much control you have over animated objects for non-combat purposes.

Wind instruments probably wouldn’t work but I’d assume mechanical instruments could work, such as accordions or drums.