It was self sacrifice. He gained nothing except to be restored to what He did have before... the glory He shared with the Father before creation. You minimise the love of God by suggesting there was self interest.
“To wit, that God was in Christ, reconciling the world unto himself, not imputing their trespasses unto them; and hath committed unto us the word of reconciliation. ”
2 Corinthians 5:19 KJV
Unfeigned Bible
There was nothing Christ received as a result of His sacrifice that didn't include mankind. The further we go into this discussion is revealing, for it shows how far away you are from truth. Denying the existence of fallen angels and of the devil... denying the prime purpose of Calvary was for the redemption of man... claiming the sacrifice of Christ was founded on self interest... denying the Divinity of Christ... denying Christ's true Sonship to His Father. You are in a deep mess. The further we go, the further you expose your apostasy.