Nemo, Nemo, nemo when it comes to HT and WAF the two shall never meet. I have the BP7001's and even I need a SVS NSD 12/2 to get the real deep bass. Since you are in a "prediciment" where the wife will rip you a new one if you buy any new gear, may I suggest you go covert.
Buy some bass shakers (transducers) wait till she goes out for a few hours, and install em in the couch, then when she comes home and feels the couch shaking, either you won't get her off the couch (cause she's having to much fun

) or she'll ask what you did. Just smile and tell her you turned up the bass in the towers a few notches and hence you now have added bass. If she's like most women, she'll be none the wiser and you'll get some decent bass.