Question...
Does anyone here have any recommendations for compact, small cardio exercise equipment? Something that takes up space in use, but which easily folds away, like those treadmills that can fold up, is also an option. (No non-recumbent bikes, plz, those things hurt me!)
I'm just looking at things that take significantly less floorspace than the recumbent bikes. My current bike needs about 6' x 3.5' of space.
I'm just looking at things that take significantly less floorspace than the recumbent bikes. My current bike needs about 6' x 3.5' of space.

no subject
Rowing machine have any appeal to you at all? There are some compact ones.
The setup you propose---bike + WII/step---sounds excellent. You can switch off, even, do 20 minutes on each.
As a source for equipment, Craig's List can be quite good. I got my Lifecycle that way.