Get Rid of Everything
Yep. Start over. The kids get a do-over every once and a while, why shouldn't you? Instead of stressing over how you'll fit one more piece of furniture into a room already bursting with the detritus of everyday life, call a local charitable foundation, and have them take the lot. No more worrying about that table with a wobbly leg, the jam stain on the couch cushion and the sticking door on the entertainment center. Save the electronics and the family photos, the rest you can replace (probably more inexpensively that you might think), and start over fresh.
This time around, use lots of area rugs and install couch slipcovers. Now, doesn't that feel better? With the room empty, isn't it amazing how spacious it looks? Ah, now you remember what it was you liked about the space in the first place, huh?