So i am back into receiver design mode for the time being and figure i would try a different band pass filter topology. Elliptic filters have some rather nice attributes. Steep skirts for a low order filter, a relatively fixed level of attenuation in the stop band at the expense of some ripple in the pass band and stop band. The other major con is non linearity of the phase response. How much of an effect that will have on a desired signal is yet to be determined. The filter design below shows a 3rd order elliptic filter, if i can build something that looks something like that with acceptable loss figures, then it might be a good candidate to replace the weakly attenuating double tuned filters with a Butterworth response that I was using.
