Considering most event cycles he's around 18k-20k, then you're looking at completing him for about another 4k-5k. As for other ninjas to go for, it mainly depends on what ninjas you currently have or what playstyle you like to play. Considering you already have 30 frags of 5 kage madara, I wouldn't not suggest going for him. He's a pretty good support ninja and he goes well with a Naruto 6 paths and other lineups