OP,
New speakers are a great idea for the next upgrade. Speakers really impact the sound of your system, so are worth really investigating. You should audition them. You want speakers that really connect with you. I would recommend listening to: Sonus Faber, B&W, Magneplanar, (lots of warm power required to drive these), a higher level Martin Logan, Dynaudiio. If you can spring for something in the $5K ballpark you are going to have speaker of tremendously greater potential.