I personally around 15-20% on elevator, 25-35% on ailerons and 40-50% on rudder. Like everyone said its a feel thing, and depends on how much throw you have on each surface. I think the main thing is to keep the feel sharp enough to maintain definition in your flying, but soft enough so that you can remain smooth in the flight.

I know that there is quite a variation between pilots, so ultimately its really what you feel most comfortable with. Its good to get some setups from others, and try them out to get a sense of what you like, then fine tune it to where you are most happy.

Renegade, you can usually activate rates with stick position, so for instance you can probably have full aileron stick activate the rates for your snap. I don't know for certain the 9303 can do it, but that functionality has been around for years on other radios so I would expect that it can do that.