mankind becomes angels
Actually, Jesus said that the resurrected would become LIKE the angels, who do not marry--he was answering a question about resurrection and marriage, not trying to describe purposes.
I look around and see that there are many types of animals in this world, and many varieties inside each specy. The Bible actually lists several types of angels, and I imagine the list is not exhaustive.
I think the creation of man is unique. Our capacity to 'hold' the Divine is even greater than the angels, I think, because of the gift of Christ, who is considered worthy of all that God is worthy of. This is difficult to grasp because it is staggering. Likewise staggering, angels are called servants; the redeemed (an innumerable crowd) are called heirs with Christ.
bebu