Honestly, if people wants her to be sub-dps it's better to give her 2x Noblesse + 2x Blizzard or 4x Noblesse, 4x blizzard is meh on her specially together with that weapon.
Xingqiu is good but imo he's better to be with someone like Chongyun for frozen and shatter, though to get high numbers from it you will need elemental mastery on Big Chongus.
For the same "safer playstyle" with Xingqiu, I prefer Fischl because you're not too close to the enemies, electro-charged intermittently stuns enemies and you get to constantly proc lightning smite.
Melt reaction and Superconduct is probably where Ganyu will shine most, just because she can proc cryo even if she's not on the field.
For constant Melt, Diluc and Klee will probably be the best main dps you can have but actually with her on your team you can now abuse the new weapons from Dragonspine, specially the Dragonspine spear for Xiangling mains (if it's better now against Crescent Pike-san I'm not sure, though 200% atk dmg/10sec is not so bad) and Snow-Tombed for Razor mains.