[NanoDuke]

Yes, that's valid, but I don't think it's more intuitive. It's easier to colour code whole numbers than deal with decimals and scientific notation.

It depends on how you want to think about it. kg/kW is saying how much weight is being shifted per kilowatt (therefore a smaller number is better), and then how much money is being spent to get that figure.

In your case bigger numbers are better, in my calcs, smaller numbers are better.

That's the beauty of mathematics. Both calculations are correct, just depends on what your preferred method is. I know I've seen some car reviews state power-to-weight figures in either kg/kW or kW/kg.