Do you need different bass patterns, or just a fuller sound? I'll assume that you use the Drawbar setting 888800000 for bass. You can Try adding the 2 2/3' to that setting and that will give you a fuller sound.
If you need the bass to be louder, you can always push in the lower manual drawbars by 1 or 2 degrees and leave the bass setting full out, then you'll just have to step on the expression pedal a little more
You can also have your tech change the foldback point on you upper manual, so that the bottom octave is deeper. I think that would be a lot easier than playing shout runs with your feet.
As for bass pedals, you can just play the normal shout pattern with your feet. its hard to do, but i've seen a few cats do it. Maybe you can try omitting the heel and doing it all with your toe. That works for some people.