NW 23rd Ave for window shopping and restaurants. Check out Salt and Straw, Grassa, The Matador, Stepping Stone, Tea Chai Te, or Lucky Lab.
There are many wonderful hiking areas around Portland and the Gorge. We recommend this one for the fully Powell-themed weekend ;) Other hiking areas include Forest Park, Mount Tabor, Council Crest, and Tryon Creek. The waterfall corridor in the Gorge has several beautiful waterfalls and hikes; however, to visit, you will need to take a shuttle or obtain a permit here: https://www.oregon.gov/odot/waterfall-corridor-permits/pages/default.aspx.