Before you buy other speakers, give yours another chance.
1. Make sure your speakers are placed appropriately. This
is a very good starting point. Make sure your speakers are a good distance from walls.
2. Rerun Audyssey. Make sure to measure the 6 position starting with the MLP and no more than 24" apart. I strongly suggest to read this
from a very well known AVS member.
3. After Audyssey is done, the first thing you should do is go set your speakers to "small" in the menu's speaker setup. Audyssey probably set them to "large". This is common for most room correction software.
4. A good place to start with your crossover setting is at 80Hz. This is the most common and used setting.
Also, some members here, including myself, find that when you set your Dynamic Volume to "Day" the dialogue seems to be "louder". I only use this settings for watching tv personally.
All of this should take you no more than an hour.
Let us know your impressions