Originally Posted by Steamer

Not usually the case. I think it's safe to assume that people will adjust the reach to the pedals when they switch to short cranks so that they have the same bend in the knee at the "bottom" (max extension) of the stroke. At least they should, and especially so in the OP's case. With proper boom extension / reach to the cranks, short crank arms do reduce the hip angle at the top (min. extension) of the stroke, which is what the OP is after.

OP - just get some short cranks unless you specifically want a pendulum type device (which you haven't mentioned so far; don't be distracted by me mentioning it if that's not what you want). Bolt-on shorteners are a bit of a hack, and add lots of Q factor which is often non wanted. And having one crank longer than the other is also probably not a good idea.