I have an '02 SANTE, and a landlock. I am a total newbie when it comes to surfing of any kind.
I tried stock ballast, with the front tank full, starboard tank full, and port empty, and it was not big enough for me to surf w/o the rope.
I have about 600 pounds in lead I will use next time I go out to see if I can find the sweet balance of weight. (I know you said no lead, but you will need more weight if it is additional sacks or people.)
I ride on the starboard side also so that helps with the CC prop rotation.