I don't understand how you can compare the price of gas (which you convert into an equivalent $/kWh price, no issues so far), with the price of electricity, without trying to account for how long or how often either heating system has to run for... it's almost certainly not the same amount of time.

For example, let's imagine an experiment where 2 heating systems are tasked with doing the same thing -- let's say, to keep a 2000 sq ft home at an even 70F degrees, when the outside air temperature is 0F while the ground temp is whatever-it-is:

- How much gas would the gas system consume, over how many hours, to maintain that 70F temp? Maybe it uses X1 amount of gas, over Y1 hours, for Z1 price of gas, so you can multiply that out.

- How much electricity would a heat pump consume, over how many hours? Maybe it uses X2 amount of electricity, over Y2 hours, for Z2 price.

You're only comparing Z1 and Z2, how could that possibly tell you the whole story? Heat pumps can be >100% efficient (I've seen claims of up to 300% efficiency in ideal conditions), while gas maxes out at about 95%, so I don't know why you wouldn't try to measure/estimate the X and Y variables too, and why you'd only focus on the Z.