I honestly dunno what 3peso's rationale for nerfing Extra Attack was, tbh - at the very least, I've not seen anybody complaining about it on this thread (unlike, say, Maintenance)
Seems that it's considered a problem area with JP players, judging from comments on the BBS link on the JP wiki.
Also, is Chen even remotely useful? I haven't read many good things on her. I wonder if I can rep someone in my party with her, if I knew how to actually use her. Cause I really do want to make Yukari as overpowered as LonelyGaruga has made Tenshi.
Ah, well, to do
that you'd have to plan your entire party around taking advantage of Yukari, and to a lesser extent the Yakumo Clan as a whole. Like, I'll give a quick rundown of my party and the roles.
-Keine: MT buffer for when I want to attack with both Iku and Tenshi (considering replacing her)
-Momiji: Instant Attack character, 20% Flying racial damage bonus, 50% ACC bonus for high EVA targets or low ACC attacks like Explosive Flame Sword
-Rumia: MT healer, 20% Human racial damage bonus, can apply all status/debuffs post-Awakening with excellent delay
-Aya: Guaranteed first turn, provides buffs before the boss acts, occasionally Divine Grandson's Advent for getting the finishing hit on a boss before it can act
-Mystia: Secondary Instant Attack character for IA Healer or other strategies that involve using a spell card with Momiji, provides debuffs on successful evasion from the back
-Satori: 24% elemental weakness damage bonus, secondary user for buffs from Iku or other characters
-Reisen: MND debuffer for Iku's Celestial Maiden's Blow, can apply all debuffs with high accuracy (her usefulness has been really low recently)
-Sanae: 30% SPI element damage bonus, 20% Youkai racial damage bonus (39% post-Awakening, Super Youkai Buster is 16%), ST healer and all-stat buffer, small MP recovery post-Awakening
-Miko: Passive 8% buff increase from the backline, miscellaneous damage dealing/tanking with Maintenance clone (considering replacing her)
-Akyuu: 50% MT Boost post-Awakening, 16% elemental weakness damage bonus (stacks with Satori),
90% 81% rate resurrection tank with no delay, can grant 1-hit invincibility on dead turns or to protect Tenshi from powerful attacks
Basically everyone besides Reisen helps Tenshi, and Reisen can still activate Ninja's skills or debuff a boss to make it slower and less damaging. Some of the characters are also useful as secondary attackers, like Momiji (Rabies Bite, subclass spells), Rumia (Moonlight Ray), Reisen (Mind Starmine, Discarder), and Miko to a lesser extent (I've only used Dragon God's Power with her because Tenshi needed Murakumo's Blessing for the fight). I used to use Eiki instead of Miko, for bosses that Tenshi and Iku both had a hard time against (namely Shredding Amnisieri).
Anyway, you can basically divide character selection into two groups.
1) Characters that help Yukari (and the other Yakumo Clan members) deal damage, take damage, and otherwise support them in combat
2) Characters that fill gaps in their offensive abilities and/or take advantage of their supporting abilities
At least, that's how I would go about it.