Despite the information given, it's very much unclear what lets some builds win over others. In particular, I found a situation (the Spar Mines) where the game really wanted me to equip a lv1 Chalk Rune (granting +1s Shocked Duration) instead of a lv2 Storm Rune (granting +5.2s Shocked Duration and +41% Lightning Damage, on my lightning-damage only build). Somehow, equipping the apparently worse gear made the difference between winning and losing? This made no sense to me.
Poking around a bit more, I've found the issue. Most enemies have a 'wrong answer penalty', a huge nerf to damage (sometimes -90%) if the player doesn't have the exact intended build equipped. This is incredibly unfun; instead of it being a game of trying to make a build that beats the challenge ahead of you, it's a game of trying to guess a secret code that the developer left cryptic hints about.
If the player can devise a non-standard build that works, either through unexpected interactions or brute force, you ought to let them. Giving a huge nerf whenever the player doesn't do exactly what you wanted them to do is just bad game design.