There is an 80 acre botanical garden in nearby Silverton. Close to that is the Gordon House - the only Frank LLoyd Wright house in Oregon. There are tours daily in the summer.
The library building was designed by Finnish Architect Alvar Aalto and also has one of the largest collections of Aalto furniture in North America. Most of the chairs, desks, tables, cabinets, shelving and light fixtures are of Aalto design. If that isn’t enough of a draw for you there is also an odd little museum on the property where you can see the world’s largest porcine hairball. https://www.mountangelabbey.org/
The monks also have their own brewery: https://www.mountangelabbey.org/benedictine-brewery/
Mt. Angel is weird in its own right, and is home to the largest Oktoberfest in the pacific northwest. It also has the largest glockenspiel in the US which plays at 11 am, 1 pm, 4 pm, and 7pm daily. It’s like a half-empty Disneyland village.
A little bit further afield is the Enchanted Forest, recently voted the best family-owned amusement park in the US. The park was created and hand built by Roger Tofte over a period of seven years in the late 1960s. The park first opened to the public in 1971. Early success led to many expansions over the last half-century, mostly built again by Tofte by hand. The Tofte family still owns and operates the 20-acre park, with three generations of the family involved in the day to day operations. Weird enchanted fun for adults and kids alike. https://www.enchantedforest.com/
Adelman Farms has an open house during peak peony season which is exactly when you’ll be in the area. There are 30 acres of production fields, a 2 acre peony display garden, and indoor displays. There is no food available for purchase on site but picnics are encouraged. https://peonyparadise.com/visiting-info-map-events
If you are in need of tacos on the way to or from the wedding, then Woodburn is the place to stop. The downtown blocks of Woodburn are like being in Mexico but in a Normal Rockwell-esque American small town. The high school has a mariachi band. The no parking signs are in spanish. Try the squash blossom tacos at El Tule.