While I agree that a bike shop is needed EOTR, closer in, I was surprised not to see one go at the Arts Walk near Catholic U. Metro station, Met Branch Trail, young people with disposable income. Seems like a dream location. Maybe someone will open one somewhere else in all the new development blowing up up there.
Another spot that I thought would make sense was some of the retail space at Nationals Park. They could do tie-ins with baseball games ("bring your bike in before the game, pick up after the 7th inning"), serve the Yards Park area (and Anacostia - "First shop over the river") and still be pretty far from any other shop. Lots of that space still sits empty, and the Nats are likely eager to rent it.
But then, I know nothing about bike shops or real estate.