I've only played for a couple of hours so these really are "impressions".
Positively i'll say its probably PDS's best release. Very few bugs and they are mostly minor that i have seen. There seems to be enough generic and western european content to keep most fans happy, at least for a couple of weeks. I surprisingly like the UI colour and set up. I thought it was a bit modern in the dev diaries but it works well and is less tacky than a thematic scheme might look. The cycling of the map modes on zoom works well. The amount of "meme" is really overplayed on the reddits and marketing, ive only played a few hours but the flavour reminds me of early CK2 rather than late Glitterhoof CK2.
My main negatives at the moment are i find there is often an overwhelming amount of information on screen between the side panels, the alerts tab at the top and how wherever you put your mouse seems to open one or more information popups its a bit cluttered.
I thought the 3D characters would be more memorable than the 2D portraits but i find the opposite. I cant remember any of the characters by image, they all feel very similar. This might be until i am more familiar with the differences though.