There is no easier country to travel in on a bike in Europe than the Netherlands. The bike paths are well marked and you can buy high quality maps that provide all the route planning info that you need. Plus the Dutch by and large speak English. I worked on a factory floor in a province called Gelderland. There were 30 guys working on the shop floor and over half of them spoke some English.
Personally I would probably avoid the larger cities. Nothing wrong with them but the cycling is much better, in my opinion, in the countryside. Once you get out of the 2 principal provinces (north and south Holland), you get to really great countryside and it is easier getting in and out of the smaller cities on a bike.