Deciding on a "swap spell" key

This is not so much a coding problem as a gameplay one. I'm creating a wand with spell slots that can be cycled through to select a spell that has been bound to the wand. Currently you can press Q and drop the wand, causing it to detect the item and cycle the spell list forward (or backward if you are sneaking). However, this has its fair share of problems and inconveniences, and I recently realized that I could use the actual swap key and detect when the wand was put into the offhand to cycle spells instead, making the whole system far less janky and preventing accidentally dropping non-wand items on instinct. While this seems like the obvious thing to do, I have worked very hard to create complex systems that allow you to cast from your offhand as well, which led to cool combos with offhand spells and mainhand weapons (though these are kind of OP sometimes). Making wands mainhand-exclusive would simplify my code a lot, but I would lose plenty of work and concepts for mechanics like summoning weapons from your mainhand. What should I do?