multiple scenes is the right point to start with.
there are two options:
1: hold down the activated scene (A or B) button and flip through the scenes.
I do precisely what you say by assigning track-related effects to trigs 9-16, so this might be a way to remember which effect sits where.
2: assign one scene to button A and one to button B. You can then fade between them and flip back to normal by deactivating one (or both) scene buttons.