I propose a new location for a city, that will enable us to seal our external border and maintain stable relations with the Germans with a stable border.

Port Khan has Condelescent Rice with crabs, an inland lake directly connected to the ocean through the future harbor, which can be used to cover ships during future city sieges. Another advantage is that any German moves will be locked to the Eastern Isthmus alone, so we can minimize the garrison in the area.

So I suggest we use our settler for Port Khan, and then worry about filling in our center later, in line with an external settlement policy first.

The reason I don't want to found a city so far north is that I fear adding too many cities will increase our horrible deficit even further. I don't think we'd want to build the additional settlers needed to fill in the rest of the eastern coast behind it. This would leave that land open for Roman or German settlers, who would found a city behind our lines.

Look closely at the map, we can effectively seal the eastern continent by placing that port there, as culture would fuse the gap very quickly.
No open border policy of course.

They'd certainly have more than enough time to put a settler through that gap, plus I'd hate to loose any trade routes we may have by closing our borders.

We can still trade with closing our borders.

We can still trade with closing our borders.

Closing our borders will make us lose all foreign traderoutes, but if we're going to adopt mercantilism, that doesn't matter.

Also the city in itself has enough goods, an inland lake to cover ships and move troops internally as well as closing the Essen border.

If a German settler move internally, we just culture flip them very quickly.

I still think our external borders are important.

I think grants proposed site is fine, we may end up invading germany so if they build and develop cities, we don't have to do it!