It is definitely one of those things where a lack of difficulty actually hurts the narrative punch. It feels like you are bullying an old man.

I think MSQ trials like Shinryu or Tsukuoyomi are sufficient for an MSQ trial. They are not hard in the grand scheme of the game but it's enough to make sure sprouts are awake when they get there in the story. Make it feel like you had to fight to get to the next plot point.