Oh man were to start? I will with your questions first:
Would we spend billions on reversing the aging process?
By now we would have had (biologicall immortality)
http://imminst.org/book1/
Would soldiers and other people who risked their lives for their jobs, be highly paid, and well respected?
Perhaps soldiers wouldn't be needed, in a completely free of mystical non-sense world, there would hardly be any wars, wars are not profitable, are irrational, and *Life* would be held as the highest value, so wars would't make sense. However for other jobs that may put people in jeopardy of harm, or fatal they would defenetly be highly payed & very much respected.
Would we be running out of space to put our cryogenicly frozen bodies?
Cryogenics would have been dismised with the advantage of having biological immortality available, all diseases would have cures, nothing would have held back the human intellect.
Would we be more concerned with the health of our planet, if we knew god wasn't coming to fix things?
By now the comcept of god, would have been LONG FORGOTTEN!! however the health of our planet would be good, because the highest value would be life, so life would have been the main objective to keep and preserve of our (hypothetical society) sure we would have had bumps along the way but we would have cleaned up, held the ones responsible, and adapt new methods of doing things for the betterment of our earthly enviorement.
That we are about 2500 years behind of were we could have been.
For instance by the time of Jesus birth man has his first flight in space, by the time of his death, we would have been to Mars, Jesus perhaps would have been a great architect, that totally revolutionaised the art of building tall mega buildings.
By today, we perhaps would have had to look forward to living 1000's of years, death would be rare, traveling to other solar systems for vacation, who the hell knows. Its unfathomable.
Godless.