あとシャワーが水飛沫になるやつも重いので切るor量を減らすのも負荷軽減に良いかも
var go = GameObject.Find("p_item_showerhead/shower_root/n_shower/LiquidShower/Pool");
go.GetComponent<ParticleSystemRenderer>().enabled = false;
//go.GetComponent<ParticleSystem>().maxParticles = 100;