Rickenbackers are very responsive to the type of string you use even different brands of round wounds will sound very different, flat wounds also sound good on them, try backing off the neck pickup just a little bit it will give you more bite in the sound, they are usually very bassy with both pickups on full. A lot of times new ones come with high action, they sound better with the action a little on the low side to me anyway.
I definitely agree about the action. For me the ric sound is low action and hit the strings really hard. The ric growl is enhanced, not hindered by copious amounts of fret buzz.

