To be influenced by a magazine and, say, a Swedish theme, unless it resonates with you, it seems kind of odd and influenced.
Avoid spending too much on one thing.
To have a 9-foot sofa in a small room can be kind of treacherous.
People get trapped in the way things should feel and less focused on the way things should function.
Be judicious with your budget and buy things that are going to last.
Think of how much furniture you need. What's the best way to have it be functional in a great way? If it's in groups, define it.