I have an idea:
Red Tunic - Protects against Heat, reduces Fire attack damage by 50%, increases Ice/Water attack damage by 50%.
Blue Tunic - Breathe underwater, reduces Ice/Water attack damage by 50%, increases Fire attack damage by 50%.
Green Tunic - Does nothing, allows normal attack damage for all elements.
Basically, have tunics that protect against certain elements while making you vulnerable to others. Also, instead of temples that have a single "theme," mix and match the types of enemies you'll encounter so that you have to change up the strategy.