C0R1 Premium Linnea Bina Zibai team comparisons - Illuga/Xilonen/Gorou
Constellations: C1 Illuga - C2 Xilonen - C6 Gorou
Linnea, Columbina and Zibai are all C0R1
The DPS is calculated across 4 rotations.
I later found out that my Zibai did a bit more damage with a Crit DMG circlet when in the Gorou team.
Also Illuga has not been ascended past level 80, but even if lv 90 the difference it would make would be minimal (~10k DPS maybe?).
My assumption is you should only ever play Illuga over Gorou if he is C6, Gorou buffs are likely to be better if they're both C0-C5.
Xilonen should be a very good option if you have her C2, and a viable choice if you are running a double hydro team (ex: with Yelan or Aino instead of Linnea).
The DMG increase from using a DEF goblet will vary for each account, and will also depend on the substats of the artifacts being compared. But it will be good to keep in mind while farming the domain.