Have you considered the hose modIJ It gives the short beans something to fall against and the reel can then brush them into the auger evenly. It's dirt cheap and really works well.
try taking old vynl siding and weaving it between the teeth of the reel. wire it in and it will act as a bat reel, per say, this wrks really well in rowed beans. but can be run full length of reels too. good luck
I bought a Crary Air Reel and works real well on the shorter beans. Granted it is not cheap but I am very happy on my hilly rolling ground where the hilltops have shorter beans and low areas are thicker. The airflow also keeps the beans moving off of the cutterbar but doesn't blow the rocks in the rocks are easly seen and not be assuming that the clump of beans is only a clump and not a hidden rock (night time horrors)! That hose idea looks interesting and not a lot of money to invest in but I still think an Air Reel is a nice investment.
I use the hose mod on a 800 Gleaner head and it works great in short beans and it also keeps out some rocks which is nice and now for the best part, it cost next to nothing and it works!!!!!