I really, really, really, really, really, really, really do not want to see pops in the Europa Universalis series.
Victoria III is a society sim that's interested in economy at the point in history when consumerism, resource management and mass politics became a powerful global force. Without all three of those ingredients I don't think pops are necessary or useful (and they are inescapably a huge drain); even with all three of those ingredients I don't think pops are the only or necessarily the best way to model the things Victoria is interested in.
Europa Universalis is not a society sim, is not terribly interested in the economy, and is not set amid the industrial revolution. Pops would add nothing useful to Europa Universalis that couldn't be achieved with less complexity and computational overhead in some other way.
I think it's reasonably well-accepted that each of Paradox's major grand strategy games has a central "offering" based on the historical period it represents: Crusader Kings is a grand strategy game, but more than that it's a game about feudal lineage and internecine dynastic politicking. Victoria is a grand strategy game but more than that it's a game about mass politics and industrialisation. Hearts of Iron... something something warfare. It's fairly well-accepted that by comparison Europa Universalis lacks a key central identity and is kind of just a game about painting the map.
This means two things, to my mind:
Europa Universalis begins with the final collapse of the Roman Empire, the unravelling of ecclesiastical absolutism in Europe, the acrimonious end of perhaps the most famous feudal conflict in the Hundred Years War and the dismantling of the über-feudal entity in Burgundy. From those beginnings in the late medieval period Europa Universalis spans the breadth of the early modern period, charting the fracturing of supranational ecclesiastical orders, the centralisation of feudal realms, the unification and calcification of rough natural borders between "culture groups" and concluding with the first total wars seeing massive armies of conscripted citizens fighting on behalf of centralised Westphalian nation-states. The shifts in the structure and organisation of political entities across the Europa Universalis period are absolutely enormous, and a lot of them (unlike the shifts in the Crusader Kings period, often driven by climate and technology) are discernible and even influence-able at the macro scale where we sit as players.
- Europa Universalis could (probably) be improved by having a central identity for the design philosophy to be built around; from movies to architecture to cookery, things are better when there's a central pillar to bring it all together, and;
- Europa Universalis's hypothetical core identity needs to be formulated and implemented in such a way that it doesn't ruin the game for the audience its built who like it because they can paint the map.
So I think the key central identity that Europa Universalis is built around should be a world that's changing underfoot even as you work to dominate it.
I think every mechanic in Europa Universalis V, so far as is reasonably practicable, should be designed so that the incentives and the ways you engage with it change over the course of the game. Things that were a good idea in the early game should be a really bad idea in the late game; things that are a great idea in the end-game might be a huge gamble in the middle, and so on.
With that in mind, I think a key mechanic that needs to underpin the above is centralisation. Europa Universalis should in large part be a game about balancing the amount of control you want to have over your lands and resources against the costs and difficulties of managing all that land and resource. And how do we make that fun? By organising the game not around pops, which represent individuals who were largely irrelevant from the beginning to the end of the time period, but around estates and subjects.
So that's what I think should be the core concept of a future EU5: it should be relentlessly focused on making the game-world and the "rules" change over time. It should achieve that primarily by making the key concern of countries, alongside warfare, be centralisation, and the player should be able to implement their strategy for centralisation (or decentralisation) and mess with their enemy's strategies, through a massively expanded system for estates and subjects.
I think on the one hand this would make Europa Universalis a vastly better "history game" in that it would actually reflect history rather than forcing you to play as an idealised Westphalian state the like of which barely existed by 1821, let alone 1444 and would satisfy the map-painter crowd by allowing them to paint maps to their hearts' content with the added ability to adjust and collect modifiers by playing with estates.
Things I would like to see redesigned around this core concept
There are four major game elements that I think need to be completely overhauled and rebuilt around the core concept of "change" and "centralisation".
I have specific proposals for each game element, but this is a really long post already and no one actually likes reading other people's ideas for game design philosophies, so I'll leave it here.
- I think internal politics need to be completely removed from EUIV (which won't be hard given they barely exist) and carefully reassessed bit by bit to ensure they interconnect, create interesting strategic choices and change over time.
- Trade and wealth needs to be reassessed to a) ensure that it's not just an inflow of money bolted on to the side of your economy like it currently is in EUIV, b) that the wealth of your country and people rather than just your treasury is a strategic concern, and c) that the important types and sources of trade and wealth change over time.
- Technology, "ideas" and government reforms need to be removed and completely reexamined.
- Unit types and recruitment need to be redesigned from the ground up.
I agree that pops are not entirely needed... IF the diversity in the population is modeled in some way. People in the forum wants pops because they don't want a return to the 1 province - 1 religion - 1 culture thing.
Pops aside, I completely agree with the rest of your post. One thing that always bothers me in EU4 is how religious vs humanist is modeled. This is very tied to the centralization aspect that you commented.
- Beeing tolerant and accepting diferent cultures (even in your grup) should not be a free "no rebels play": you should have to make consesions that lower your centralization/absolutism -> local governance
- There should be a purpose for wanting a one faith one culture in your realm as it happened in some empires -> more control.
-> Play for example with minimum autonomy and governing capacity cost on provinces that have a different majority.
-> Represent nobility, clergy and merchants from different relevant cultures/religions in your empire, not only generic estates that follow the interests of the crown.
On the other hand, I like the aproach of meiou and taxes that some have commented: what you don't gain because of autonomy shouldn't be voided, it should remain in some local administration (local nobles, local mayor...) that uses those resources to improve that region. This is a way to have your estates doing something actively.
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