In my opinion saved means a lot more than just going to heaven after you die. Salvation is the good fruits of our lives here and now. The Old Testament practically says nothing about us going to heaven or hell, but it says a lot about salvation. Especially in the Psalms. Abraham, Moses, and the Prophets were totally committed to God without any real mention of afterlife rewards. In my opinion we should love the Lord with all of our heart, soul and mind even if there wasn't an afterlife.
All right, but I'm not sure what salvation even means apart from eternal life. You are right, the concept was vague in the Old testament, and blessings for living according to God's will had more to do with peace and prosperity in the present life.
But as I see it, one of the most important messages of our faith is that, in order to know who God truly is and how trustworthy He truly is and how worthy of our love He truly is, the problem of death must be addressed and it was, in very definitive terms by Jesus and His sacrificial death and resurrection. In fact, everything He said and did was a revelation of who God is, of His heart, of His will, for man.
Jesus laid down his life in order that He might raise it back up, dramatically resolving the prospect of non-existence that looms over our lives and threatens to render them meaningless.
And salvation
does mean a lot more than going to heaven BTW, especially considering the fact that we hardly know what that means anyway. In any case, salvation means to fulill our very created purpose as we draw near to God and nearer and nearer to His own likeness, as we become perfected in love of Him and neighbor to put it another way. This is our purpose, our telos, our wholeness, our integrity and happiness, our raison d'etre.