Note: [C1] is recommended for DPS build, meaning Oz can still attack even off field. With [C6], you'll be able to have additional electro damage that scales off 30% of Fischl's ATK.
There's also an animation cancelling technique with Fischl DPS, after 3 or 5 basic attacks, rapidly tap r twice and you'll reset your whole combo, but only use this for animation cancelling when you're out of stamina.