Something we all agree on? That all believers will be resurrected first to be with the Lord and given a glorified body at some point? So who does that leave but the unbelievers that have not been resurrected yet. It is only until the white throne judgement day of God that those though out time that didn't believe will have been raised from the dead to be judged, along with the believers, who are to be rewarded their deeds or misdeeds and to see who is in the book of life.
You mentioned something about immortality. Who was it given to? Well I think all christians would say that it is only given to believers. The reason I wanted to address this is because it makes a difference in how you look at it. If you believe that unbelievers through out time are asleep in the ground and when they are resurrected...they will be supernaturally clothed back into flesh and blood once again. Only then does all that you said make sense. For now, when they are thrown into the lake of fire, their human flesh can burn to death into ashes and then be stepped on under people's feet.
But another group says that only believers will receive an everlasting body, but the dead unbeliever's spirit is raised from the dead to stand before God, because flesh and blood can not stand before God's throne in heaven. When we talk about John the Revelator being in the spirit when he had the visions about heaven...is that what form these unbelievers are in when they stand before the throne to be judged? Is it only a vision and not physically there? Or is there a part of the body...our essence or spirit that can be taken to heaven for the day of judgement? For if an essence of the person still exist, then that part of them can witness the lake of fire...forever.