Happy to provide some insight -- of course, your mileage may vary, because VIR and Proteus aren't released yet, but based on my knowledge of electricity, this is how it should all work out.
Remember, when your coil and wick are flooded, there is a LOT more juice to take the power from the coil -- this means that at a particular voltage, the temperature of the coil and wick and juice will be lower. When your coil and wick are dry, there is a lot LESS to heat up, so the temperature will skyrocket (burning cotton in most mods).
What VIR does that VV and VW can't do (remember, VIR is a mode) is sense when the coil is pulling too much power, creating too much heat, and it throttles power back, 1000 times a second. It will also sense when a coil isn't getting temperature up high (means too much juice) and will ramp up wattage to try clear the problem.
Wattage isn't that important anymore -- as long as VIR can send enough power to get to your preferred temperature, but never higher, you will never worry about wattage again. Even resistance isn't as important, as long as you stick in the range that VIR can buck and boost voltage to support at a given temperature.