Finally have time to play some Civ. Playing Tokugawa.
He's AWESOME! And for reasons I had not even realized, but the synergies are top notch. Apart from the self-evident stuff, there's also:
-> You're encouraged to grow your population fast to unlock more/earlier districts;
-> Aqueducts and Dams seem particularly useful for the pop growth (plus easy adjacencies);
-> Harbors/Lighthouses are really important for the Trade Capacity, Housing and Food, also Colossus;
-> Industrial Zones/Electronic Factory will fit perfectly around Aqueducts and Dams.
-> This playstyle also fits naturally with the two most powerful governors in the game, Pingala (pops) and Magnus (pop growth, industry).
Not entirely sure if this much synergy was even intended.
As expected, 100% Loyalty around Capital is not all that useful by itself. It is very map dependent. The one situation in which it's very strong is if you have nearby civilizations, in which case you can forward settle with no problem. That is a pretty strong ability in that specific situation. The ability should read 100% Loyatly +2 Amenities, as amenities are simply more reliable. (I find +4 Amenities a bit excessive tbf).
Yeah, I'm playing through with him, and you really can try to synergize. Basically I'm playing a mini-game to get my capital as big as possible and get as many districts. I think with the Communism internal trade card plus the great merchant that gives a gold bonus, I'm at like 11 food/7 production/19 gold per internal route, plus I forget if I'm at +6 or +7 science/culture too. The only downside is that it makes the civ a very spread out one - to get the most of the route yields, I can't pile up the traders in the same city too much.
The only parts that don't synergize are wanting your cities packed together as close as possible to benefit from district adjacency, but also want them big to build more districts so they don't tend to have lots of tiles to work. The 100% loyalty isn't a huge bonus overall, but the other parts are nice enough that I don't mind. Even that is nice to let you do a little forward settling early if you need it.