To me, the problem with the IZ is that it largely just “adds” production to an city, rather than actually boosting the production of that city.
It barely adds any, though. At least the buildings. Unless you're Japan, the dutch, or Germany, IZs themselves aren't even that good if you don't run the card.
Yeah, there should be something that makes a Big City zone more powerful than a little town with just a few pop to run a campus. Maybe zones could get some sort of benefit for number of other zones in a city? Just spitballing.
That’s a very cool idea. Would synergies well with GEs that give an extra district slot and also Germany.
Back in summer 2017 there was a lot of discussion about how to help tall cities be more than the sum of their parts- often including things like Power Plants giving production to each district in the city, etc. I think most of the T3 buildings could use similar "utility" powers to aid big cities, like how the stadium grants tourism.
GEs could also use some tweaking- there's 3 wonder rushers, and 3 that affect the IZ buildings (2/3 to give more production)- they feel like they should be a little more "production-y" and have beefier general perks.
3/18 rush wonders
3/18 boost IZ buildings
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3/18 boost space race projects
2/18 give tile appeal
2/18 give housing and amenities to a city
2/18 give +1 district and a eureka
1/18 boosts EC regional buildings
1/18 gives the culture bomb
1/18 grants free walls
Small great person peeve: way too many give the eureka for computers.
Anyways, onto the GEs. One third of them are very "GE" type bonuses. Personally, I dislike the emphasis on the space race. With Sagan and Kwolek, that's a lot of Great People focused on that single victory. With the mausoleum in play, it also makes them a little ridiculous.
What I dislike about the housing GEs is that they don't boost growth, just the capacity, and so can "fall flat." Jane Drew alone would suffice for this category IMO.
The +1 district ability is also not
that strong in the grand scheme. It's certainly useful - high production city, low growth, lots of key district sites- but it would be nice if they gave some kind of other benefit (like instantly complete a district they're standing on) etc.
Tile appeal is also something we could probably handle just 1 of- and many heavy industry players have ruined their appeal with mines around the IZs. The culture bomb ability is clever, but I wish it had a little more punch with it. Joseph Paxton is very strong - he's +2 amenities in 9 tiles, or +4 in 12 tiles. He's a mini colosseum/maracana, and
really pairs well with the robber barons policy.
Compare with, say, the great merchants, 12/24 of which directly give you gold or trade routes, and a further 4 give you unique luxuries. (3 of which you can sell!) The remaining third have some more utility type effects. Great engineers, instead, have 1/3 as very GE/wonder/production focused, and the other 2/3 doing utility. Give me hammers or give me death!
The other big issue with GE balancing at the moment is the Mausoleum, which can make some effects really crazy (+200% to space race) or do nothing (can't get that eureka twice...). I love the wonder to death, but it's not the healthiest for game balance.