This is almost certainly a small minority view, but from my perspective as a European based in the Bay Area who may be moving back to Europe next summer, the most important aspect would be geographical proximity to a decent university where staff and faculty can get away with speaking only English.
In short, I'm wondering what place/group/organisation/activity could do for rationality in Europe what Berkeley does for rationality in the US?
Soon, we'll have LWCW in Berlin, which I hope will be an occasion to do some networking among people who think seriously about developing rationality communities. But in the meantime, let's do some brainstorming.
Important note: in comments to this post, please use only consequentialist language. For example, say "If we decided for the base to be on Malta, then X would happen" instead of "I think it should be in Malta, because..."
Of course, share anything else that you think is relevant to the topic.
Also, see you all in Berlin :)