The only other option would be to have reserve days for this kind of tournament so if there is a day of rain to wash out a game, it can be played the next day. Lots of logistical issues with ticket availability and venue availability that comes with that, though. And with the current format, it wouldn't work because there's too many games. Unless the format changed (to something like a group format (2 groups of 5 etc, top 2 go through to a semi-final/final)) then it'd free up a lot of days spare.