Apologies if this is old news as the change to the mission improvement actually happened well before the April rebalance.
So, haven't played Spain in a while (ever) as there was little incentive to do so; probably others in the same boat. Obviously the highlights of the rebalance for Spain are the extra yields from trade routes (which you can further exploit with Owls if you play SS) and the bonuses to intercontinental setting. So I'm hyped to play them, but as I'm looking over their traits in preparation, I noticed something...
Spain's mission improvement does not list ANY placement restrictions; most UI either can't be next to each other or only on flat, but the mission doesn't seem to have any placement restrictions (curious about floodplains, marshes, rainforests, and woods, but even assuming no to all of them...) I'd say there's 4 tiers of mission placements, excluding tile base yield. From lowest to highest, Tier 1 is on the home continent not adjacent to a campus or holy site, Tier 2 is home continent with that adjacency, Tier 3 is off-continent without adjacency, and Tier 4 is off continent with HS/CMP adjacency. The +2 science from the late-game civic is not to little but definitely too late; the game is pretty much decided at that point and the big influx of science is good but isn't going to have much impact other than shaving a few turns off of victory.
Now, the most you're ever going to get with a holy site adjacency is 6 if it's completely surrounded by mountains. Arguably it could be more if it's adjacent to one or more natural wonder tiles AND has multiple mountains or a lot of woods, but that's one in a billion map luck. Even on the worst (my tier list) positioning, instead of surrounding a holy site with mountains, NW, and forests, you instead surround it with tiles, preferably hills, that don't have resources (or ones you plan to chop.) Then completely surround the holy site with missions on those six tiles. Each tile will generate 2 faith and the six tiles cumulatively generate 12 faith, which is the same faith bonus as the maximum adjacency of the district while running that policy card. But, being adjacent to a holy site doesn't give more faith, it gives a measly +1 science. But that means sacrificing the district adjacency to completely surround it with missions not only gives you equal or greater faith than you're likely to get from adjacency, but also each holy site indirectly gives you +6 science. A similar but weaker argument can be made for campuses as multiple fissures and reefs can make it's adjacency quite a bit more than six and can be doubled with a policy card but again, would you rather have an extra couple of science, or a couple less and +12 faith all while allowing you to use that policy slot for a different bonus? Strong case towards the latter.
And this is extremely more potent with the off-continent placements. First off, they get +4 faith instead of +2, so completely surrounding a holy site or campus with missions and working those 6 tiles gets you 24 faith per turn, in addition to +6 science. But the real difference-maker is the +1 food and +1 production to the tiles, turning shabby flat grass into respectable 3F/1P tiles with tons of faith and some science, and hilly grass or plains tiles into 3F/2P or 2F/3P tiles which are high priority tiles even before considering the mass amounts of faith and small but consistent boosts to science.
Anxious to test try it out, but going in I'm thinking with the exeption of the first city or two (as they aren't unlocked until Education and the start bias means good capital campus adjacency--- which helps get to Education), completely foregoing campus and holy site adjacency in lieu of surrounding them with missions means never running either district adjacency or buildings cards allowing to slot in more trade route boosting cards, and that this may be the best yield-porn civ in the game!
So, haven't played Spain in a while (ever) as there was little incentive to do so; probably others in the same boat. Obviously the highlights of the rebalance for Spain are the extra yields from trade routes (which you can further exploit with Owls if you play SS) and the bonuses to intercontinental setting. So I'm hyped to play them, but as I'm looking over their traits in preparation, I noticed something...
Spain's mission improvement does not list ANY placement restrictions; most UI either can't be next to each other or only on flat, but the mission doesn't seem to have any placement restrictions (curious about floodplains, marshes, rainforests, and woods, but even assuming no to all of them...) I'd say there's 4 tiers of mission placements, excluding tile base yield. From lowest to highest, Tier 1 is on the home continent not adjacent to a campus or holy site, Tier 2 is home continent with that adjacency, Tier 3 is off-continent without adjacency, and Tier 4 is off continent with HS/CMP adjacency. The +2 science from the late-game civic is not to little but definitely too late; the game is pretty much decided at that point and the big influx of science is good but isn't going to have much impact other than shaving a few turns off of victory.
Now, the most you're ever going to get with a holy site adjacency is 6 if it's completely surrounded by mountains. Arguably it could be more if it's adjacent to one or more natural wonder tiles AND has multiple mountains or a lot of woods, but that's one in a billion map luck. Even on the worst (my tier list) positioning, instead of surrounding a holy site with mountains, NW, and forests, you instead surround it with tiles, preferably hills, that don't have resources (or ones you plan to chop.) Then completely surround the holy site with missions on those six tiles. Each tile will generate 2 faith and the six tiles cumulatively generate 12 faith, which is the same faith bonus as the maximum adjacency of the district while running that policy card. But, being adjacent to a holy site doesn't give more faith, it gives a measly +1 science. But that means sacrificing the district adjacency to completely surround it with missions not only gives you equal or greater faith than you're likely to get from adjacency, but also each holy site indirectly gives you +6 science. A similar but weaker argument can be made for campuses as multiple fissures and reefs can make it's adjacency quite a bit more than six and can be doubled with a policy card but again, would you rather have an extra couple of science, or a couple less and +12 faith all while allowing you to use that policy slot for a different bonus? Strong case towards the latter.
And this is extremely more potent with the off-continent placements. First off, they get +4 faith instead of +2, so completely surrounding a holy site or campus with missions and working those 6 tiles gets you 24 faith per turn, in addition to +6 science. But the real difference-maker is the +1 food and +1 production to the tiles, turning shabby flat grass into respectable 3F/1P tiles with tons of faith and some science, and hilly grass or plains tiles into 3F/2P or 2F/3P tiles which are high priority tiles even before considering the mass amounts of faith and small but consistent boosts to science.
Anxious to test try it out, but going in I'm thinking with the exeption of the first city or two (as they aren't unlocked until Education and the start bias means good capital campus adjacency--- which helps get to Education), completely foregoing campus and holy site adjacency in lieu of surrounding them with missions means never running either district adjacency or buildings cards allowing to slot in more trade route boosting cards, and that this may be the best yield-porn civ in the game!