I can't say for sure, given that a bit more than half my income comes from KU, so I'm predisposed to remain. But I looked at your rankings and it seems that you may be well-posed to take the plunge into wide. As far as when, if I were you, there are a couple of things I'd consider. First, how much money do you think you'd make from KU between now and when the game supplement releases? If it's negligible, then you don't lose much by choosing to go wide now. Also, you've got more advertizing options by going wide, at least I think so. If you have the means, you might make sure your books are wide ahead of the new release and line up some promos on your 1st in series, to see if you can juice sales.
Please bear in mind that we're all seeking what works to find sales. I don't have a crystal ball. Good luck.