All survival trial ninjas except Suigetsu are worth 10 points per frag so you should aim to 5 star them. Team 7 and the rest are worth 10 points per frag including Sai. Kimimaro, Kabuto and the sannin are also worth 10 points although all the jonin are worth 5 points so you shouldn't bother with them too much. I couldn't find the list to link it here but it should be posted somewhere in the forum.