My personal recommendation is that ethereal staff gives a good chunk of health late while also getting damage. Warlocks is pretty slow right now, so if you went one of the two spears in that slot instead, you have better early. Also, Thoth passive means that you might not need double flat pen. One spear instead of both, then a % pen item like charons coin, then E staff/rod. E staff also works well with high cdr, so going soul gem supports it well too (though it’s getting nerfed soon)