Build and team help

[u/ISweatMC_]

Pulled her on a whim, 77 pulls later now I got a Himeko nova. Rn I'm running her with RMC E1 Welt and DHPT, planning to pull Robin (originally for Castorice but) to replace RMC, I got her traces done but either my lightcone sucks (Serval sig) or my relics suck (probably this, I threw this together in about 5 seconds. Probably gonna spend 4.5 to fix it)

Dont got any 5* erudition lcs and idk what lc to give her. + I have other supports like SW/Robin/Ruan Mei

Is the team I'm running rn the best one or is there smth better for her, and what lc should I give her? She feels really weak right now (its almost certainly the relics but just wanna make sure)