I don't think ETs would be something good but who knows. Catholic Church stated that if they exist we should bring them the word of Jesus and that we would be brothers and sisters:
Jesuit Father Jose Funes, director of the Vatican's astronomical observatory, said in an interview published Tuesday that believing in alien life doesn't contradict faith in God.
"Just as we consider earthly life as 'a brother' and 'sister,' why should we not talk about an 'extraterrestrial brother?' It would still be part of creation," he said.
It's a big universe out there, said McMurry University physics professor Wayne Keith, "big enough for other forms of life besides what's on the Earth."
"I don't personally see any conflict between belief in God and the possibility of life elsewhere in the universe, and I've always thought it a bit odd that some people would interpret the Bible in a way that precluded life beyond the Earth," Keith said. "... To pin your faith on something not existing is to set yourself up for a crisis of faith if we ever did discover life elsewhere."
Catholic church: Faith in God, alien life OK Abilene Reporter-News
I don't know where I'm standing in this topic but I guess I'll think about it when ET comes home again.