I think that there should be a system in grounded where players could combine the effects of 2 trinkets (max) together with a balanced twist. The trinkets should act as the following; the Dominant Trinket (aka the effect you want to mainly focus on), and the Non-Dominant Trinket (aka the effect you want as a secondary effect).
I also think players should only be able to combine only ominent badges with specific trinkets. No Sarah's charm combinations. However the combo items would be; fungal charm, suspicious ice cap, spicy charm, insulating larva spike, and all ominent badges. The debuff should be worse depending on the Non-Dominant Trinket. I don't know coding, but I think this could improve the experience of Grounded.