I think for me to go back to North America, I think I would feel the need for an express purpose to feel motivated to move that far, like grad school or something to give focus to such a huge undertaking. Otherwise, our life is too good here and I am home here, just like I am there. But why bother with the stress of moving when we are happy here and with a good life quality? I know we could have a good life quality there - I just can't be bothered with the stress of moving.
I am grateful that health care is a non-issue between Canada with universal health care and the UK with the NHS.