Indeed, I bet that is HUGE difference and a marked in provement!
I recommend download the free ETF acoustic software trial here:
http://www.etfacoustic.com/
It's an impressive and powerfull tool to measure your room acoustics. Of course, we will not know just WHAT the improvement is over your pre-treatment, but it will tell us a good deal about what you are working with now.
I am very interested in your findings!
Good luck!
Joel