I had a lot of ideas when I redid my basement.......all cost a lot of money. "Old Money" style takes a lot of wood paneling, art deco required expensive marginally useful furniture. I even wanted to duplicate sandstone walls and ornate pillars and trim to approximate an Egyptian tomb.
After the delusions subsided I realized that these themes were campy and too far reaching for a farmhouse basement.
I decided simply to put in a "wood" (laminate) floor and then painted the room in a bold color (orange).
It was a train wreck until I got furniture, drapes, pictures, etc........which muted the boldness nicely. As far as themes go.......were there isn't one. I have a mishmash of nautical/fishing pictures/paintings, Bavarian mementos, dead deer skulls, sports pictures, etc.
I like it this way.