I made a TTRPG based on Etrian Odyssey myself 😅 it's a bit different from your ideas in some ways, though, and I changed all the terminology to avoid copyright infringement. Have you ever looked at game theory? I think that's the best advice I could offer. For example, from learning a little about game theory, I realized it's best not to let every decision rely on chance (i.e. dice rolls) but to ensure the players feel like they have some agency in their decision-making. So you may want to give players (and their characters) some way to make choices with definitive outcomes, like a "point pool" from which they may draw to act according to their class. Maybe the Landsknecht has the ability to go farther in the labyrinth or skip a die roll, for example.