I personally think there's a more direct link between the US administration and Russia, in line with the rest of your points. I think it's more than "dictator-jealousy fueled encouragement", although what that "more" is I'm not entirely sure, and I'm not sure the differences between the possibilities matters in the end.
I really think it's hard not to read [about] Foundations of Geopolitics and the history of Viktor Yanukovych, the ties between the latter and Trump, and not conclude Russia's tendrils in the US, England, and elsewhere are far deeper than is generally acknowledged in the press.
I lost a lot of trust in most media to cover this issue appropriately when people in the UK started mysteriously dying and zipping themselves in body bags, and the coverage was a collective shrug. Why they would report something like that and then with a straight face conclude an article with "police say there's no evidence of foul play" is beyond me. But then again how the Mueller investigation got spun as an exoneration is also beyond me as well.
I know it's often seen as dismissive or shallow to blame the media for things, but I really do place a huge proportion of the blame for our current mess, at least in the US, on news outlets and media soft-pedaling what's been happening for the last 10 years. A lot of what people trust became propaganda, and a lot of the rest of it chased that audience around for clicks.