Going to be difficult to go back and defend all those titles in the autumn - after Vienna I remember reading that he said something like 'I always come back to defend my titles', but nothing like that was said after Shezhen. Who knows, the humidity might be too much there though for him to be inclined to return, but he is defending more from there than he is from Beijing, but more points available from the latter. But as Vienna and Valencia are reportedly switching categories in 2016 he might be more inclined to go to both this year and then continue returning to Vienna once it is a 500. All speculation on my part of course. Putting a schedule together must be quite complicated for the players.
Yes I do recall that Shenzhen was quite a climate challenge. I suppose as far as the top players go they can usually depend on either being offered a wild card, or asking for one since it's likely to be granted even if it does mean putting a lower-ranked player out of the tournament, so can leave making a decision until 2 or 3 days before it starts.