what's a good daily prize to get in the winter event?
None of them seems to be really useful
I think one of the more popular is the Sleigh Builder, a 2x3 that can give 15 goods a day.
Otherwise, I think it all depends on what you may be missing in your city. On one world, I just can't get a Hall of Fame to drop from Daily Challenges but, if the prizes I've seen don't change, I'll be sure to get one from the event.
Having said that, I also found it quite easy to look at one day's special and decide to save my stars until the next day ... and then the next ... and then the next.