Wallace Falls is one of those hikes I end up doing almost every other time I'm in Washington! It honestly doesn't matter what season it is or what the weather is doing—I've hiked it in sun, rain, and snow, and it somehow always feels a little different each time.
There are three main stopping points: Lower, Middle, and Upper Falls. Personally, I'd skip the Upper Falls. It's a bit of extra effort for a view that isn't nearly as exciting as I expected, and I think Middle Falls is easily the best payoff. Between the Lower and Middle Falls, there's a small pavilion and picnic tables that make a great spot to sit down, relax, and have lunch before heading back.
No matter the conditions, this is a hike I always recommend and one I never seem to get tired of.