Kerio..i agree that you need to address the speaker/room interface before entertaining new speakers. Before treating the room, you can get potentially great enhancement in your in-room bass response by merely playing around with speaker placement. I am attaching a link to an exerpt from Robert Harley's (editor of TAS) book "A Complete Guide to High End Audio," which has a detailed section on speaker placement, starting on page 7 of the 21 page booklet exerpt. There may be other helpful hints in there as well on common room treatment suggestions as well. But first I would try tweaking your speaker placement. One suggestion is to pull your speakers out further away from the backwall, as that should definitely reduce boomy bass. Here's a link to the exerpt, which can also be found at the TAS website: http://media.avguide.com/excerpt.pdf
Hope this helps
Hope this helps