Figured I share a little about my recent experience with sound treatment. It's been something I've been contemplating working on for a couple years, but only since joining taxi have I really been motivated to really get on the ball a bit.
My room is a fairly small office area in my basement, and it's a bit weird shaped, but mostly rectangular. I kinda figured it had a few issues, but I didn't really know to what extent. I decided to drop a little cash into some auralex bass traps and sound absorption panels. Getting them mounted was a pain at first, but once I figured out a decent, non-permanent solution that worked, it wasn't too bad.
During the process, I also uncoupled (not sure if this is the right term) my Yamaha HS6's from my desk by putting some sound panels underneath them. Apart from creating a barrier for more accurate bottom end, it also helped raise the level of my monitors up about 3 inches which ended up being a lot better for overall placement.
After it was all said and done, I'm a little blown away by what I'm hearing. Some of it could be placebo I suppose, but I'm able to hear stuff I was not able to hear before. Everything actually seems louder. The bottom end definitely has appeared out of nowhere it seems, and there is a clarity that I didn't have before.
Suffice it to say, I'm really happy I spent the money to help get the room a little bit less troublesome. I'm sure it probably has a few issues, but it feels lightyears ahead of where it was before. If you're debating between dropping a few hundred bucks on a new set of plugins or some sound treatment, my vote is the soundtreatment by a longshot.

Andrew