I believe it is imperative that we seed life wherever we can as soon as we can. I think those that are opposed to this idea are simply not looking at the larger picture. Certainly, we as a species have many many failings. But observe the great good that we are able to accomplish when we set ourselves to do it. We must assume, for our own good, that we will continue to grow and learn, to make mistakes and also learn to fix them, as we have done for thousands of years. To learn to use our environment to the best of its ability, but without damaging it beyond its ability to repair. Seeding the planets with the basic life forms needed to allow the development of a compatible ecosystem will be a way of paying back our own creation, whether deliberate or not, and adding to the amazing and immense beauty of the universe. What a glorious gift to give. And in time our descendants will travel to where we planted and discover wonders we cannot have imagined. If God does exist, he would be pleased that we valued his gift to us enough to give it to other worlds.