What ever your taste really, but I do love to see period houses reflecting the age in which they are built.
So ours was built in the 30s and I have one room in particular that tips it’s decor to what I would describe as glam Hollywood of the 30s, so long swishy white curtains, very pale apricot walls, parquet flooring with an Art Deco design around the edge, off white rug and white and black fireplace that is Art Deco in design but not tiles. Ornaments that I found in charity shops and auctions etc of the period.
The rest of the house is also done with the 30s in mind but not so glam, very homely. Our snug is wallpapered, with matching curtains in greenish duck egg blue. The sofa and chairs are stripped and plain with colours that pick out the rug and wallpaper. The rug is American but an Axminster design.
Hall and stairs has a dado rail beneath which is a Morris wallpaper, bit early really but I loved the design and the stair carpet matches the colour.
The dining room is papered with a heavy figured wallpaper which we paint according to our taste at the time, at the moment it is called Matchstick ? a sort of off white beige sort of colour, matching the dining chairs. The rug is a red Turkish wool design so very busy, everything else is plain with red picked out in cushions in a rocker and chair.
Most of my friends and neighbours have much more modern taste, and their homes are often with very clean lines and everywhere pale and pristine. I do like it and could happily live with that, but ours just sort of evolved into what it is.