Steadicam JR - more ergonomic grip?
 

After finally getting around to practicing using my JR I was wondering if there exists a more custom molded handle accessory? I've found that a firm grip is essential and the standard flat stick is less than perfect for this. I know it needs to be ambidextrous but it could still be this and more form-fitting too.

Or do I just need to get used to it?

Try sneaking your pinkie underneath the handle for a bit more support; plus you can use the pinkie and ring finger of your other (operating) hand as support for the grip hand as well (obviously leaving the thumb and first finger clear for operating the guide).

I have been wondering if you could adapt something like the chisel handle pictured here to cover the existing handle.