England having double trade routes was a stopgap introduced in a patch...
Yep, it was. Trade route stacking was clearly not part of the original plan for England. But stop gap or not, it really worked and fitted the civ. Other civs (like persia) get bonuses to trade routes, others can do unique things with trade routes (Dutch, Cree). England just got more of them.
And I say ‘more’, not double, for good reason. Only coastal cities benefit. And only if you build two districts in those cities, which requires pop, production, and forgoing other districts like campuses.
One suspects there will be no changes in the near future, we have what we have.
Agreed. This isn’t going to change in the short term.
...What a harbour is to me up until now realistically, is half a commercial hub ...So [the RND is] sort of not half price because it gets half of what other districts get... but it does get it early and the other bits of the harbour are unique.
England also basically gets a discount for Commercial Hubs: CHs are worth more to England than other Civs because, with trade stacking, they retain their trade route even if you have a harbour. For other civs, if you have a harbour, the CH has less value because you don’t get a TR for that district.
To me, more CHs (and a backdoor discount to them) fits England as not only a seafaring / colonial power, but also a mercantile / financial power.
England has an incentive to settle or conquer cities far away from its core homeland. The problem is that with loyalty, you would just be losing those cities in a matter of turns to the "natives" of those other continents. This would particularly be an issue with the AI agenda. So, they wanted to give england some kind of ability to counteract that.
Settling or invading foreign continents is only situationally useful. And even with England’s bonuses, it’s a real hassle - eg build a settler, wait ten turns for it to get to the other continent, then you still have get that city online (which is possibly harder mid game); so, a long time before any return on your investment. Or go agressive: you can beeline caravels and frigates, but then your melee will probably still be only warriors or maybe swordsman, and you’re behind getting campuses and dominating your own continent. So, get all the campuses and swordsmen, redcoats etc first - but then those foreign cities have time for walls and units and tech and put up a hell of a fight.
And, after all that, your new city is harder to supply and defend because it’s so far from your core cities; and in R&F you’ll also presumably be fighting off loyalty from other established civs (does England’s loyalty boost give it an edge here, or just counteract (ie zero sum) the disadvantages a ‘colonial’ city has?).
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I love where England is in terms of power in Vanilla. Firmly mid-tier. You have to work hard at the start, but are then rewarded with a solid mid and late game if you succeed. The expansionist bonuses are great, and situationally awesome, but with trade route stacking England also has other strategies open to it. Getting rid of this bonus, even with the loyalty buff, seems... unnecessary.
All that said, there may be other changes which buff England in R&F. All these new sea resources and features may make coastal cities stronger, and mean your harbours get more adjancies. Trade routes being restricted for everyone may mean England, with half price harbours, may still have more TRs than the average civ. And it’s hard to guess how loyalty and governors will actually play out.