Your Sims will automatically wear formal wear at wedding and pre wedding partys. For family gathering, there's also an alternate version available where they'll choose party wear. Bach parties remain untouched as they are already set to the appropriate party wear.
The True "Instant" Cheat or Trait that will make your gameplay a bit less frusturating. I scour all the file that labeled instant from all the platforms there isn't any choices on actual instant so this is only page that promotes that.
This Mod let's Sims choose a Raincoat, which they'll wear autonomously when it is raining and they are outside. It will protect them from getting wet, and they won't need an Umbrella anymore. They will get a random Moodlet, when wearing one of the Raincoats.