I see significantly less immunity on lesser champions and whatnot.
Golem has gained the ability to last longer than short few seconds in 1 on 1 situations.
They have become a usable option for "Immune Fire, Lightning, Cold, Magic" mobs without becoming overpowered. I would never use it unless I have to because it takes so long to melee down the mob with a sorcerer even with a halfway decent weapon. It at least works well enough though now that if even after elemental drain the mob is still immune to fire/lightning I don't have to lure it into a corner and teleport out and have to skip killing it altogether.
Its still rough with magic/poison enchanted though with all those acid puddles stacking up so fast. Even lightning enchanted isn't as bad. This part is not a complaint though so don't get me wrong. I just know to bring down a metric shit ton of potions when I see one of them.
With how little risk there is when stone cursing a mob, there has to be a serious downside and having it be very slow killing is perfect in my opinion.
Not that I think it needs it at the moment, but if there were any other changes that increased its usability, you might counteract it by doubling armor or giving a damage reduction ability to it? Just a thought.