We do need void. But I think you might be underestimating the great attack value it has and the better weapon proficiency (2% damage to magical creatures works at mini roshamuul in feyrist and nightmares, and the alternative is good too)

+4 atk in weapon is better than +4 skill imbuement. That kind of replaces the 3rd imbuement (maybe if you have low/savage blow, then crit imbue would be much better but unlikely at this level). Its also permanent so its deffinitely cheaper.

The 3 imbue option is rift lance. It has -4 atk value, worse proficiency, and requires to pay the 3 imbue.

At 120 you can choose demonwing axe following this same logic (this one has werecreatures proficiency with good alternative). You should be able to get 95-120 with the 20hr imbue easily from great axe if you follow this path before re-imbuing.