You obviously find the idea of humans on Mars and beyond romantic and stirring. So do I, to a point. But I also find the idea of a vastly superior AI exploring the Cosmos and making contact with similar ETI also romantic, exciting, and in many senses more practical and likely.

Point is, the distance problem is the same both for AI or for humans - and if the 'distance problem' is ever solved (through some breakthrough in our understanding of the interaction between matter and space), then it would make interstellar travel possible both for AI and for us. You takes your pick ..

Another way of puttin this is: if we send AI off to explore the galaxy, you do avoid potential problems of cro-magnons with car-keys going mad and slugging it out in some hollowed-out asteroid - but it will still take from decades up to tens of thousands of years to receive any results.

BTW I am a great afficionado of robotic missions .. I would love to see an interstellar probe. I've followed Robotic missions since Mariner 9 and even earlier (Luna 16 & Luna 17)

(thanks for your interesting views, and links)