Next I searched for benches with cubbies. We'd still get a seat and some storage -- it would just be exposed. In addition to a general search, I looked at kids furniture stores. You'd be surprised at what you can find at places like PB Kids and Land of Nod that works for adult spaces. What I finally settled on was the Winslow White Twin-Size Small Cubbie Bench from Overstock.com ($100.99 each, free shipping, 20" h x 36.25" w x 15.75" d), which, interestingly, is marketed for kids rooms.
The two cubbies arrived in about a week and were easy to put together. I did it myself and it took about 45 minutes for each one. The final product is surprisingly sturdy and they have a nice presence in the room. I topped them with pillows from Persnickety Home made with Anna Maria Horner's Sketchbook in Blue fabric ($26 for two, plus inserts), and used some woven baskets I had from Pottery Barn to store craft and office supplies. Cashy loves sitting there with me and at looking out at the big, old maple tree in our front yard. And they just help make that room feel more finished now.