Another chance doesn't guarantee success. If people know there's no risk of failure, then there's no tension. I'm never really worried that bad things will happen to any of these characters, and no matter what choices I make it will always work out.
Legit. It's not as if the MC's a god who knows every cheat code in his new life. Granted RNGeusEx could do it for plot convenience, but by using the fact that this is another chance in life to avoid mistakes doesn't make a good argument. Saito's not a miracle-maker. It doesn't also mean easy success, as you said. Dunno why you're getting downvoted. Might compromise and just toggle NTR stuff off for the snowflakes LOL. Might kill them because their imaginary "waifus" are getting fucked by other men.