Highlighted weapons are free options.
This section assumes you have unlocked Qiqi's Lucid Revelation buffs from the Witch's Revelation Quest: Instruction of Curious Form.
Qiqi is capable of providing not only extremely strong healing, but also decent Cryo Application and Energy generation. Not only can she now generate energy when the Herald of Frost hits enemies, but now her Skill has near 100% uptime, and performs coordiated attacks off-field.
Additionally, Qiqi is capable of providing potent buffs to the Stellar-Conduct reaction, so she is an excellent member to pair with Sandrone (who is currently the only character capable of enabling the Stellar-Conduct reaction, and thus creating a Polestar Field).
Building Energy Recharge on Qiqi helps her use her Burst for better healing, as her Skill does not heal a whole lot on it's own.