After many, many attempts I was able to form aesthetic Netherlands starting as Flanders.
Flanders is a very difficult country to form the Netherlands with. It starts outside the HRE, and all of the territory (except Flanders and the Picardy region) is in the HRE. It is also a vassal to Burgundy.
So basically to pull this off I had to find a way to get both England and France in my independence war with a claim in Picardy ready to go. As soon as the war fires, you're able to make sovereign decisions. Royal marry France and use the war time to suck up to the current emperor (which, for whatever reason, has been Brandenberg since the 1450s) and join the HRE.
It's important to do this before the war ends, because you need 121 relation with the emperor to get 3 province Flanders in. Austria 90% of the time is a 1444 rival to France, and you are considered France's ally in the independence war, so +100 relations +25 same faith -25 rivaled to ally. If you have 5 province it's impossible (140+). You either need Austria to not rival France, a non-Austria emperor, or you need to start subsidizing Austria for 10yr/max even if it means going into debt. Subsidies usually get Austria to set you to friendly, which makes Royal Marriage (+25) possible. If that doesn't happen, you must take out loans to simply bribe Austria over 121.
By the time the war ends, I had both provinces under Calais and I gave land to France from southern Burgundy. I believe I also liberated Luxembourg. Burgundy should be your primary focus. Burgundy must be destroyed as quickly as possible for aesthetic borders. It's also a good idea to use your diplo to set your intentions to conquer aesthetic borders, and favors should be traded in with France for trust as much as possible (while keeping 10 favors in your pocket).
If Burgundy isn't destroyed, you have a big fucking problem. After 1478 the Burgundy Inheritance fires and the absolute worst case scenario is France getting it. Sometimes, however, it can result in lowland countries being freed from Burgundy. You should be doing this anyways. Take 1 or 2 provinces from Burgundy, and then release Hainut, etc. It helps to keep a 1 province buffer between Burgundy and France so it can't claim them (Champagne).
I ended up forced-vassalizing Holland, Brabant, and Hainat, then diplo-annexed them at once. I further vassalized Utrecht, Gelre, and Freisland. The Dutch half of the Netherlands was formed through vassal feeding and diploannexing. Antwerpen was the furthest east* I directly annexed.
I'm at a point now where I'm bored. I don't like colonizing and I don't have the ideas to set up. I enjoy killing England and refuse to ever ally with them. I often release Wales and use it as a march so I can deploy foot troops safely into the island and kill the shitty English troops for free humiliations to keep power projection over 50.
Usually, I play in Africa or the Middle East where aggressive expansion is less important. One of the hardest things to do while expanding is suck enough ass so a coalition doesn't form. It really helps to have extra diplomats.
but I'm sure that'll be in next week's dev diary along with the Russian Fascist Party and the Kadets.
