Minstrel was overperforming (pun intended) so here are some balance changes (nerfs):

Strum Damage (up to 25% reduction)
Prior 4 5 6 8 10 12 30 80 220 640 1800
Current 4 5 6 7 8 9 22 60 165 480 1350

All Song Mana costs (increased at tier 6+)
Prior 50 58 66 74 82 90 100 110 120 130 140
Current 50 58 66 74 82 90 110 130 150 170 190

Song of Resilience Damage Reduction (up to 30% less)
Prior 10 12 14 16 18 20 21 22 23 24 25
Current 10 11 12 13 14 15 15.5 16 16.5 17 17.5

Song of Resilience Healing (up to 33% reduction)
Prior 4 6 7 9 12 15 16 18 19 21 22
Current 5 6 7 8 9 10 11 12 13 14 15

Song of Battle Damage (25% reduction at all tiers)
Prior 0 0 60 105 150 195 540 1350 3600 9000 24000
Current 0 0 45 80 110 150 400 1000 2700 6750 18000

Song of Freedom Damage (just rounded values, no nerf, now >2.5x Song of Battle dps)
Prior 0 0 0 52 75 97 270 675 1800 4500 12000
Current 0 0 0 50 75 100 270 675 1800 4500 12000

Resonance Strum Damage Bonus Per Song (20% reduction, same 1% growth past tier 5)
Prior 0 0.05 0.10 0.15 0.20 0.25 0.26 0.27 0.28 0.29 0.30
Current 0 0.04 0.08 0.12 0.16 0.20 0.21 0.22 0.23 0.24 0.25

Reverberation Cooldown Changes & Consequent Adjustments
Reverberations now have a shared 2 second cooldown instead of independent 3 second cooldowns. This is to create a choice where previously players could (eventually) use 2 or 3 of the reverbs on cooldown without having to put much thought into it. Now, players can choose to alternate between types or focus as needed. This should make the gameplay a little more engaging. However, this change results in half as many overall Reverberations so some adjustments are outlined below to compensate. Song coverage should still be sufficient so no changes have been made to duration or radius. The skill descriptions are already too long so this synced cooldown will have to be something that players discover for themselves.
1. Reverberations now count as 4 uses of Strum (previously 2) for purposes of the proc. The proc benefit of using Reverberations as often as possible is unchanged.
2. Reverberation costs are doubled: 50/58/66/74/82/90. This keeps the cost of using Reverberations as often as possible unchanged.
3. Reverberation heals and damage are now 50% stronger (rounding down on heals). While this is technically a nerf to overall output, the aoe/1v1/healing is actually quite a bit higher when focusing exclusively on the corresponding song. For example, using only Song of Freedom will deal 50% more 1v1 damage than using both Song of Battle and Freedom in the prior system (but you won't have any aoe damage or healing output when you do this).

Quality of Life
1. Starting any song when you have the ability to use all 3 will now start all songs without cooldown.

Bug Fix
1. Fixed a visual bug where Musical Notes would sometimes not disappear if used point-blank on certain types of targets.

1. Adjusted Reverberation costs again (now increases by 4/tier, was originally 5 then 3). I think I have finally found the sweet spot for mana costs.
2. Reduced the minimum speed of moving Reverberations to 0.3 (from 0.5). Increase the initial speed of moving Reverberations to 1.0 (from 0.5). Max speed is still 2.
3. Press time to change Reverberation behaviour has been increased from 0.15 to 0.20 seconds
4. Movement is now the default behaviour for Reverberations and pressing will make them stationary

Debuffs will no longer be applied to certain invalid units such as traps. This should prevent moving Reverberations from slowing down at times when they should not.

Change
1. Reverberations now speed up when there are no enemies in range (up to twice prior speed) and slow when there are any (down to half prior speed)

Bug Fix
1. Song of Freedom's Reverberation no longer targets invalid units (traps, etc.)

Balance
1. Song mana costs now increase more slowly to offset how often they can/should be used (3/tier from 5/tier, total of 10 less at tier 5)
2. Strum's cooldown has been decreased from 0.7 to 0.6 seconds

Graphics
1. Mini-Notes indicating the zone for Song of Freedom (blue) now show up a little better

Added Skill Indicator:
Overhead indicators are now shown to identify when Reverberations are off cooldown. They float fairly high above the head to accommodate health/mana/combo bars so they look a little odd when those bars are hidden. These icons draw in a top layer so they should be visible even behind walls or in a sandstorm. In multiplayer mode, other clients do not see these indicators.

Auto-Releasing Reverberations:
The tap vs hold-then-release for controlling Reverberation movement felt clunky so the skill will now automatically release when the button has been held for long enough (0.15 seconds).

Other Tweaks:
1. The lightning strikes on Song of Freedom are now slightly more blue and transparent (less visual clutter). The local player will also hear a faint zap sound.
2. X-Ray effects have been removed from most sprites so now everything looks a lot better
3. An unimportant warning has been resolved

Correction: Minstrel's class title is health regen (same values as Priest) and not mana regen as I had incorrectly stated in the mod description

Require Line of Sight:
1. Songs no longer apply their buffs/debuffs through walls
2. Reverberations no longer hit through walls
3. The projectile-destroying wave no longer affects projectiles through walls

Visual Bug Fixes:
1. The heal from Song of Resonance no longer shows the value twice to some clients in multiplayer mode
2. The single target attack on Song of Freedom now shows the lightning effect to other clients in multiplayer
3. The visual zone from the player-centered Songs no longer persist in place after a death

Reduce Clutter:
1. Mini-notes indicating Song zones are much more transparent (these were the main clutter)
2. Musical Notes are now slightly more transparent
3. Rainbow Musical Notes (all 3 song effects) cycle colours more slowly so they are less distracting and less likely to "smear" when moving quickly
4. Musical Note explosions are more transparent
5. Reverberations are now slightly transparent, but still stand out very clearly (more than the rest)

After playing to 25 in a party of 3, I have several balancing changes to share. The goal is to keep overall damage around where it was, but move some damage from the auto to the Reverberations to make them feel more impactful. Additionally, it should be easier to cover a large area in Song and land some heals. Strum should be made worth investing in too.

Party support was good except that players were rarely in range of a song/reverbs so the range and duration of these has been increased. Healing numbers felt low but fair. The time to trigger moving Reverberations felt too long so this has reduced - it should now be a tap for stationary vs a slightly longer tap (at minimum) for moving. The speed of Reverberations felt slow, but this made them easy to play around.

Strum didn't feel worth investing in but still did a ton of work at level 1 due to items. Damage has been reduced a little to cut back the scaling. The bonus note proc has been spread across levels to make Strum worth investing in. Creating Reverberations now also counts towards these procs and multiple procs can be stored this way.

The blue pulse when creating Song of Freedom's reverb did not destroy many projectiles that I expected it to so the "IsBlockable" requirement has been removed. Damage from Reverberations was quite low so this has been increased.

Changes:
1. Increased Song cooldown reduction from Harmony (10%/20% to 20%/40%, this results in approximately 10% less actual cooldown time)
2. The projectile-destroying wave when creating a Reverberation for Song of Freedom will now destroy most projectiles instead of only those that have "IsBlockable"
3. Strum's damage has been reduced (6/8/10/12/14/16 to 4/5/6/8/10/12)
4. Strum's bonus procs have been spread across levels to make the skill worth investing in
5. Creating Reverberations now counts towards Strum procs and multiple procs can be stored
6. Songs and Reverberations have 25% increased radius
7. Damage from Reverberations has been doubled
8. Resonance now increases the duration of Reverberations by 2 seconds per level (from 1)
9. The required press time to add motion to Reverberations has been decreased (0.25sec to 0.15sec)
10. Reduced Note radius bonus from Amplify (20/30/40/50 to 15/20/25/30)
11. The visuals for all pulses are now more faint
12. The debuff indicator (circle under foot) is a little bigger so you can see it on most enemies now
13. Solved some unimportant warnings

1. Corrected the damage values in the text of Strum
2. Improved the mana regen buff from Resonance (starts 3 instead of 2, increases by 1 instead of 0.5)
3. Added brief stun to Song of Freedom's reverberation (uses same durations as Resonance stuns)

Fix starting songs in multiplayer created reverb for other clients. Take 2.