Yes, with the O scale layout, I kit bashed and custom painted almost all the structures. One example is that I cut the triangle peaks off some Cape Cods, and used a second for the second floor. Added a basement section, front porch, changed the door on 2nd floor to a window and filled or made a widow's walk.
Took 2 hopitals and made a mini shopping center of them (like in my old town of Ambler). Most of the rest was custom painting and adding details.
Now I'm in S Scale and glad I didn't get rid of them, they'll look even better in S.