The universe is not fine tuned though, it is expanding and increasing in speed. If it was fine tuned as you say it would be stable and constant but its not. It's unbalanced and reactive and continually changing and it's structure is completely random in its make up. Nothing about it says "intelligent design" because the design itself is random. Now whether its the Big Bang, or the Membrane theory or String Theory or simply a Theory of Everything, man will find out why our universe came into existence and we will not stop until we do as its in our nature to find out. And if you want more proof of the non existence of god, why would god put in us that will to explore, to research and find out why we are if all he wanted was for us to accept he did it all?
And your last sentence is what I would call the death knell for all religions, the discovery of life on another planetary body. If that happens than every religion is redundant overnight. And the reason for that it is the premise of every religion we, mankind, is special in that we have been made or created. But the existence of life, even fossilised, microscopic life on another body destroys that premise. The discovery of life on another planet means life evolves and is not created and that we are not special, we are nothing more than the current apex of a carbon based life form evolving in an oxygen rich atmosphere.
And the implications of that are mind blowing. Imagine a Methane based life form evolving in an Argon rich atmosphere? Or a Silicon based life form in an Sulfur based atmosphere?