1) Shop in the redemption market and in survival trials 2) Not currently sure maybe if your ninja is at max level? 3) Its better to distribute them also in your other ninjas specially when you are above 55 which you will have 3 teams of different ninjas in the ranked battle.
I'm above Level 55 and That is what I'm facing. It gets hard distributing cultivation points among 12 Ninjas level 55+. But Thanks for these Info.