I've thought about battles in your game probably far more than I should have, but if you're still planning to continue working on this game after the jam, here's a suggestion for combat. Instead of having a traditional "battle" like in most RPGs, you should have a morality variable in game. You can encounter various NPCs in the game, either randomly or in the story, where combat takes the form of doing good/evil deeds to an entity. If you do nice things, your morality goes up and you can ascend to higher levels of heaven. If you do bad things, your morality goes down and you can descend to lower levels of heaven/hell. I imagine this as something similar to the ACT option in battling in UNDERTALE, if you've played that game. That could be a way to replace the story triggers and make "combat" more meaningful. Another thing to add, this game does feel more like a walking simulator than a proper RPG. Just putting that there with not much else to say on that.
Yes I had some kind of battle in mind without HP so I think I should replace it by morality, but because going up in heavens doesn't have meaning in story other than first part of game where the main character is completely pure and can go all the heavens down, Only bad techniques are needed. Angels can do good techniques to stop the characters. Fixed number of battles in both as story events and lying on the field. hard part that needs more thinking is the techniques and how to obtain them and levelling up in this short game that even with battles added I don't think it becomes more that two hours.
For now I'll only fix some events, and this version maybe for some other time in future.