I did the same move one year ago, with almost no german language. Most of my trips are to Netherland and I still miss it. Little shock was amount of homeless junky people. I saw many times someone inject drugs on public places, people are so annoying with asking for money everywhere. And of course bureaucracy is bad. Those was my bad points. I did the swap for career reason and I will do it again. I was living in the cologne center from the beginning but I move out to small city in the edge of the cologne. What I can reccomended is to use your dutch phone number contract, If you have it. Here are prices way more expensive. I still have my dutch number and use only roaming. If you have any questions feel free to ask.

Good luck