Even if this game is extremely grindy, it wouldn't be much of a deal if scenes were:
1- Repeatable
2- Reviewable
3- Non-blocked by changing chapters (AKA either being able to have access to scenes from difference chapters OR being able to rewind back to a certain chapter with current stats)
In fact, the game feels like an extreme linear story, where scenes are unlocked by making certain choices that will block certain others while having no way to repeat even unlocked scenes. You can't have both a linear game with no sidetracking while imposing grinding for scenes, it just doesn't fit and you need to to choose either one. Imo, since this is a RPG maker game, you should definitely consider making scenes more affordable/reachable by either making them repeatable or making them able to be played while being later into the game. Nothing sucks more to be cucked a scene because you lacked the skill lvl and then not being able to see it forever in your playthrough just because you lvled a different skill and don't have access back to that scene