So as much as I love Rin’s kit, I feel like I would’ve liked her more as a sustain/support following Harmony or Preservation. These are my thoughts (Tb counts as Servant):

Basic Attack: “Bajiquan”: Deals 100% Quantum damage to a single enemy

After using X Skill Points, enhance Basic Attack to “Gandr”

Enhanced Basic Attack: “Gandr”: Deals 150% Quantum damage to a single enemy and reduce enemy’s Speed . Target becomes “Enemy Master” for 3 turns. Allies who attack “Enemy Master” gain a stackable shield equal to 100% of Rin’s Attack plus X and Rin gains “Gem Energy”. Servants who attack “Enemy Master” will gain an additional shield equal to 200% of Rin’s current “Gem Energy”

Skill: “Jewel Magecraft”: Use multiple times to shuffle through Rin’s gems:   
“Ruby” Increase allies’ Attack and Crit Damage  
“Emerald” Provides a shield to all allies equal to Rin’s Attack plus X  
“Amethyst” Reduce all enemies’ Attack  
“Citrine” Apply Vulnerable to all enemies  
Increase Effectiveness for ally Servants and against “Enemy Master”  
Effectiveness increases each time you use “Gem Magecraft” in one turn & charges “Gem Energy”

Using/Gaining Skill Points charges “Gem Energy” (capped at 100). After using 5 Skill Points, trigger Single Target Follow-Up Attack and restore 1 Skill Point.

Archer FUA: When Archer & Rin use a combined total of X Skill Points, trigger Joint FUA and restore X Skill Points

Ultimate: “Guardian of the Scales”: Marks all enemies as “Enemy Master” for 3 turns and consumes all “Gem Energy” to trigger Rin’s gems to buff/debuff all allies/enemies that scales off the amount of “Gem Energy” consumed, and (like Cyrene with the Chrysos Heirs) provides special buffs for ally Servants then regains Skill Points.

E1: “Rin’s Pendant”: Increase “Gem Energy” cap to 200 and for every 20 Gem Energy Consumed when using Ultimate, increase Gem effectiveness by 10%. 

E2: “Jeweled Sword Zelretch”: After using “Gem Magecraft” 3 times in one turn, regain 2 Skill Points & gain 10 extra “Gem Energy” for each use of “Gem Magecraft” for two turns.

E4: “Family Heir”: “Enemy Masters” gain Quantum Weakness and have their All-Type RES reduced by 20% and further reduce their Quantum RES by 20%.

E6: “Command Spell”: Increase Ultimate effectiveness by 40% and restore 50% of “Gem Energy” consumed and restore 3 Skill Points.   
Additionally, revive all fallen allies with 200 HP for each ”Gem Energy” consumed. Revive Ally Servants with 100% HP and charge Ultimates for each use “Gem Energy” consumed (3 times per battle). Then, restore 30 ”Gem Energy” for each ally Servant

Is this my best or favorite fan kit? Not by a long shot, and I understand why Rin’s kit is the way it is (trust me, I do). But I would’ve liked it if she, as a master, had more of a support kit so I could 1) have a full Fate/Star Rail team & 2) We already have 3 Fate dps, so why not 1 Fate support/sustain instead of another dps? (And revival is locked behind E6 so don’t come after me for that)

And does this seem closer to Harmony or Preservation? Cuz there’s the shielding and reviving (again, it’s locked behind E6 so it’s not unfair), but also a lot of (de)buffing. I pasted on the Harmony symbol over the Erudition one in the pic but I don’t think Preservation would be wrong with this kit either

Rin’s Support Kit