Acheron + Ashveil might be broken in CW
Full disclosure, I do have a well-built E2S1 Acheron; however, I don't think E2 does much in CW specifically.
Ashveil's addition to CW was already a notable buff to Acheron as it made the Galaxay Ranger bond more accessible. However, as I was doing runs to get to WC40, I stumbled across something even better.
The Planetary Drill item, made with a Drill and a Battery, allows the wearer to inflict a vulnerability debuff whenever they attack.
Ashveil has a REALLY high attack frequency in CW, so if you equip him with a Planetary Drill, he prints stacks for Acheron.
Other things I look out for are Anti-Grav Boots for Pela (Double Boots), Charging Sail (Battery + Pistol) for Jiaoqiu, and Rappa/Boothill for Galaxay Ranger Bond.
Welt is great if you can get him, and I avoid Yanqing unless I need him for level 6/8 Debuff Bond. Aventurine is a good sustain since I have his LC, but I bench him if I get Welt.
It took me 4 runs to get from WC30 to 40, 3 of them were Acheon + Ashveil runs that ended with a rating of S or higher.