There are two pools for Legendary Items (LIs for short):
Class Item Pool A
Target Ballad Resist Rating
Healing and Motivation Skills Morale Healing
Raise the Spirit Healing
Bolster Courage Healing
Inspire Fellows Healing
Ballad of War Magnitude
Healing Skills Power Cost
Class Item Pool B
Target Song Resist Rating
Chord of Salvation Cooldown
Echoes of Battle Resistance Rating Debuff
Cry of the Chorus Cooldown
Song of the Dead Cooldown
Ballad of Unshakable Will Fear Resistance
Ballad of Flame Fire Defence
Weapon Pool A
Triumphant Spirit Cooldown
Call to War Skills Resistance Chance
Piercing Cry Damage
Call of Oromë Damage
Soliloquy of Spirit HoT Pulses
Rally! Cooldown
Healing Threat
Weapon Pool B
Call of the Second Age Targets
Call to Fate Critical Multiplier
Recovery time Still as Death
Tier 1 Ballad Damage
Tier 2 Ballad Damage
Target Resist Cry of Valar
Cure Fear Cooldown
So what does this mean? The Minstrel Class Item is the Songbook. I usually use my characters in raids and as Minstrel, Healing is our main job.
Minstrel Songbook Pool
•Healing and Motivation Skills Morale Healing
This legacy is the most important one, as it affects all healing skills.
•Bolster Courage Healing
BC is our main healing skill, which makes this legacy the second most important.
•Inspire Fellows Healing
A group-healing skill (with a small buffing) which costs a lot of power. For short fights and when a Lore-Master is around, I have started using this skill. Watcher and Turtle come in mind.
•Healing Skills Power Cost
Maxed out, this skill reduces power consumption by 10 percent. Certainly nice to have.
•Ballad of War Magnitude
Champions will love you for this skill, as it gives maximal 10 percent melee offence.
•Chord of Salvation Cooldown
Reducing the cooldown for an nice, instant, power-costly single-target-heal.
•Cry of the Chorus Cooldown
Even less important, but better than what follows.
•Raise the Spirit Healing
Don't know, when I last used this skill.
•Song of the Dead Cooldown
With the Barad Guldur instance and probalby more undead in the next big raid, this might come in handy. But nothing I would really look out for.
•Target Ballad Resist Rating
•Target Song Resist Rating
I don't seem to get too many resists.
•Ballad of Flame Fire Defence
•Echoes of Battle Resistance Rating Debuff
•Ballad of Unshakable Will Fear Resistance
Don't seem to make that much of a difference.
Main Hand Weapon
•Rally! Cooldown
Reduces the cooldown for rally from 30 minutes to 24 minutes. This might seem to be not worth it, but I would recommend to get this one maxed, even if it is only on a rezing-weapon (i.e. a weapon only used for this skill. I often put the weapon on the quick-bar, above the Rally! icon and swich, when I need it.
•Recovery time Still as Death
Same as above. If possible, get one weapon with these two skills. This legacy reduces the cooldown from ten to four minutes. Nice! Saves a walk up the Tower of Barad Guldur.
•Healing Threat
In most fights, threat has been less of an issue lately. But it is always a good thing to lay low, so go for this one, if possible.
•Triumphant Spirit Cooldown
I like this legacy, even though it costs a lot of power and adds aggro. A lot of aggro. Not a skill I consider to be a must-have.
•Call of Oromë Damage
•Piercing Cry Damage
Two important attacks made 20 or 30 percent stronger? Must have on your war-speach-weapon, not that important, on your raiding-weapon.
•Call to War Skills Resistance Chance
•Call to Fate Critical Multiplier
•Call of the Second Age Targets
•Tier 1 Ballad Damage
•Tier 2 Ballad Damage
•Target Resist Cry of Valar
As I said, I usually heal or team up. These skills are important for your war-speach-weapon, but less (or not) on your raiding-weapon.
•Cure Fear Cooldown
A 3m range and a long cool-down makes this skill useless in most circumstances.
•Soliloquy of Spirit Heal Over Time Pulses
Can't remember, when I used this one.