As far as rain activities, I'd say put on some rain gear and go for a ride. Very peaceful if you've got enough stuff on to keep you dry.
Do you have the transparent airbox cover? I just cut up my inner airbox and used some bolts so it's nothing under there but the filter and the cover just big enough to hold the filter on. Looks great with the transparent airbox, plus it sounds a lot better. The majority of that sewing machine noise you heard was the airbox.