I picked up EUV at launch, after having been a fan of the series since EUII. I was immediately hooked by the complex economic and demographical simulations, the incredible depth and commitment to historical accuracy, but at the same time, there were definitely some rough edges - and that's putting it lightly. Every single one of my early playthroughs, which I did enjoy while they lasted, was eventually stopped dead in its tracks by frustrating bugs, interface issues, mechanics with bizarre and usually unintended consequences, etc.
At the time that I'm writing this review, patch 1.3 has just come out, and I finally feel that I can wholeheartedly recommend this game to any fans of the genre. I've just completed my first full campaign (as Novgorod) from 1337 to 1836, and it was a blast from start to finish. The rough edges have been smoothed, the game is more stable, the UI feels more intuitive and less intrusive, and they've taken a look at some of the events and mechanics that were functioning in a way that led to frustration for many players.
Now, what separates EUV from the previous entry? The main difference with EUIV is that this game takes a much more simulationist and less abstracted approach. Every location in every province in the world has a fully simulated population associated with it, with demographic characteristics such as culture(s), religion(s), population size, population growth, migration attraction, and estate distribution (the relative size of the various social classes). This interacts with almost every single other aspect of the game, especially the economy, in a way that is very realistic for a video game, and that I find very engaging. Another example is that if you raise levies during a war and they die, you will actually lose population in the provinces that they were raised from. I don't know of any other game that goes this in-depth, even Paradox's own Victoria series isn't really comparable.
This same depth is of course also a drawback in the sense that there's a steep learning curve. You need to be willing to put in the time and effort to familiarize yourself with the mechanics, if you want to get the most out of this game. Yes, there are options to automate just about everything if you are so inclined, but most players won't get much enjoyment out of having the game play itself. Many people will be overwhelmed by the complexity and the sheer number of options and mechanics, and even if they're not, they might not be interested in the time period, or prefer the more abstracted boardgame approach of EUIV. Paradox also has a habit of adding even more bloat and complexity as time goes on, in their questionable attempts at emulating a live service model for their games.
Final verdict: if you are a grand strategy gamer with a preference for realistic simulation, this is an absolute must-buy. There is no other game even remotely like it at the moment.
If that doesn't describe you, EUV still has a lot to offer, but it likely won't grab you in the same way, and you have to decide for yourself whether it sounds like it would be worth the effort to wade through its complexity.
