Blizzardkit is decently the best, because of a few factors. He's the only kit with actual lore as a warrior, plus he's a more nervous kit, and being his mentor is more soothing to him than Willowclaw, who is harsher than she would be to a normal apprentice because he's her kin. Cloverkit is probably the least best, and then Juniperkit is second best, with Starlingkit in the middle. I hope this helped!