This last weekend I went to my third PyData, the one in London, and it's been such a great experience.
Before, I went to PyData Amsterdam, and PyData Madrid, also this year.
After the three conferences, which were very similar, but quite different at the same time, I just wanted to share what I liked, and what in my opinion could be improved. I hope future organizers can find some useful information from my ideas and thought. And that includes my future self, for when I'm an organizer.
Organization I wasn't involved that much in the organization, but my believe is that more should be delegated. I couldn't see it that much in Amsterdam, but organizers of both Madrid and London looked extremely exhausted at the end of the conference. May be I'm too optimistic, but I'd say that more people would like to help. I think a good idea is probably to find volunteers for specific tasks. For example, probably some people would be happy to help in the registration. And organizers would have more time for other things, and to rest.
Event hosts I think in the three conferences there were amazing hosts (the people who gave the welcome speeches, closing notes...). Vincent and the Italian guy (sorry for not remembering your name if you read this) in Amsterdam,Guillem in Madrid, and Ian and Emlyn in London. I think the whole conference makes a difference having hosts with great humour and communication skills.