[dsp1234]

1.) and 2.), ok. As pointed out, Windows Server containers don't have any additional licensing costs above and beyond the base host OS license. Presumably, if you already paid that cost, then you feel that it's reasonable to do so.

As for the size, I have the feeling that people that are going to run windows containers as a herd are going to opt for the nano image which is 793.3 MB. Still about 6.5 times larger than the ubuntu container image you mention, but 11.5 times smaller than the servercore container image. Particularly since the nano image is focused towards individual roles (IIS, dns, etc) which work well with the 1 task per container philosophy.

All in all, I'm not sure what the value is in comparing the two solutions (that isn't already covered in the Linux vs Windows threads). You can't run Linux containers on Windows, and you can't run Windows containers on Linux (without running an actual virtualized workload). So it seems pretty clear that you choose Windows if you have Windows servers to containerize, and Linux if you have Linux servers to containerize.