We did the same thing and added a Renogy portable 100 watt suitcase to our 200 watts on the roof, at half the wattage it can at rimes out perform roof panels if I occasionally reposition the solar suitcase throughout the day. Peak amps from roof solar occurs for about 4 hours daily, solar suitcase will do 8 hours or more (during summer) of peak amps.
Folds into less than 6" inside zippered hard case, easily stores in our passthrough storage, bed of the truck, or even the backseat. Without all the rigmarole calculations, a general rule of thumb is 100 watts of solar per battery, just as Boon Docker posted above, this works well for him. We use all the amenities in our rig, solar is helpful, thank heavens we have a genny.