I go back and forth on this one. On one hand, it does not really add anything and for a long time I did not really use it. There isn't much point without an appearance system (or a more crucial one). ...
My absolute favorite house designer is a clutter queen and it does look cool at first but I noticed the more clutter, the more issues with sims being able to complete tasks. It doesn't take long to clean up though and I get a beautiful house out of it.