Thanks for sharing! VR controllers add another level to the immersion as well as give more variety and realism to the cockpits.
My preference is to push the thumbstick in for tertiary, and squeeze the handle for secondary - it’s a bit like pulling it towards you so feels very intuitive for things like the push/pull Airbus knobs.
Good idea to assign increase/decrease to the buttons as a workaround! I would still prefer to use the thumbstick as it feels more intuitive and realistic, especially for flicking switches or turning knobs. I made a bug report about not being able to assign the thumbstick, please vote if you have the same issue