If Elon Musk (or any suitable ambitious and rich person) fancies an exciting challenge, there is a very large and ancient body of land in relatively shallow waters (15m) between the UK and the Continent called Doggerland [0].
Many years ago some people were looking into reclaiming the island and making it the worlds biggest wind farm. It is in a perfect location. Plus you never know, might be able to make it an independent nation ;). Possibly a good launch site?