Go with your strongest heroes, you have Scarlett at 4/35 so I’d try to finish her. She pairs well with Kiril’s buffs: healing and Def+ from him, and Atk- to the enemies from her. It helps survival. So I’d try to push him as far as possible.
Valen is another one I’d bring, because you’ve invested a decent amount of emblems so his stats will be good, and you can’t go wrong with def- to maximize your damage output.
As for your yellows: WU Kong is great, but he can also bite the hand of the one who feeds him. Since he’s your only 4 star yellow I’m tempted to say that you should try and bring him up to speed. But you’ll likely be waiting longer if you do that.
It’s good you kept Bane, and with emblems again I think he’s a good choice to bring. Blind effect can be invaluable when it works. If you can’t get Wu up to speed, then I’d at least try to get Melia’s skill maxed, Crit+ will also be very valuable. If not, then Kailani’s spirit link will also keep your team healthy (just use it after Kirril’s).
That rounds out your team like so:
Kiril | Valen | Scarlett | Bane | ( Wu Kong / Melia / Kailani)
You only have Kiril as your healer, so keeping him alive will be very important. Items wise I’d bring antidotes, potions, axes, and dragon (or turtle) banners. You will want antidotes as almost every boss from this point on casts some kind of negative ailment (blind, burn, poison). If you bring turtle banners, don’t use them after Kiril’s buff (wait until it runs out). Axes, don’t use them after you hit with Scarlett (wait until her atk- runs out).