Cut and pasted from my post on luniafan with changes
Pieces should be maxed. Between levels 7~10, it adds about 100 damage per skill point assuming it hits 8 times (as it should since you will only cast it in the right situations). No other skill in Lunia give you that kind of return for the skill point investment. It's silly to say mana is an issue since you are not going to spam it whenever it cools down. If you don't land it right, there is no knockback and Eir's wide open to get comboed.
Dodge should be maxed just because of the AA dodge combo starter.
AAS - Knights can play dead before the S
AA HSP - Knights can play dead before they get hit by holy spirit, then dash AS to start a combo
AA DOD - Knights can play dead before dodge, but the dodge bomb will be placed right above the knight's body so they have to wake up to it.
The most damaging PVP juggle combos should start with the most damaging skills first, and starting a juggle with a skill like dodge lets you add your most damaging skills next to maximize damage.
After dodge (lvl6 or above so it floats high), there are 4 skills you can use to maximize your juggle combo.
Full Moon Bullet: I really don't like this option since sometimes it hits 3 times and sometimes it hits 2. After skill change, it does more damage but travels too inconsistently and requires sacred wave follow-up to deal any kind of damage.
Moonlight Chain: Not really tested but seems promising. The min and max damage are bunched closer than before. Might be able to follow up with other skills/attacks
Holy spirit: All-around versatile skill. Overall damage values changed from wiki's values. Shift so your target doesn't end up hitting the wall prematurely before all 7 hits of spirit hit, follow with dash dash tears (only 4 hits reliably)
Blessed Bravery: I'm going to max this with the pvp healer that I am remaking; potentially can deal most damage out of the four even with minimize damage if you can add enough hits with shift/halfdashes even without breaking the 3 loop rule. Ok I am going to admit this option doesn't look good so far. In the globin forest stage the bravery potion gives you a lvl6 bravery equivalent buff and I noticed that my damage ranged from mid 20s to high 60s, which basically raised average damage by 2x points. That is horrible. I need to do more testing but it seems like I can't recommend maxing this instead of chain/spirit.
Tears of goddess doesn't hit all 6 times reliably so I can't recommend putting more than 1 point in it. The potential changes to it in episode 4 might worth maxing it but need to do more research.
Sacred Wave should be left at 1. The difference between leaving it at level 1 and maxing it is 100 dmg for 5 skill points. Thats not efficient.
Of course I am going to assume that any pvp eir will max bind, get lvl2~3 sleep, and max mana recovery, mana increase, and health increase.
EDIT: and of course lvl1+ fog