The Netherlands are also ideal for longer bicycle vacations. On the links-page a few suppliers are mentioned. Especially for the Netherlands, Bike&Barge is a charming solution for guided group tours.
But there is no reason really why you shouldn't adventure on your own, if you're after optimal freedom in destination, duration and tempo. In this country, and certainly in the most visited central part, you'll find towns and villages, and facilities of all kind, every few kilometers.
Possibly, if you're a bit hesitant, some advice on the preparation might come in handy. Like practical suggestions on route and accommodation. Or a little help to get you on the road, cycling with you the first half day or so. For an introduction to local traffic rules and habits, for general background information on the country.
Even coaching while you're on a self guided trip is a possibility. If you need advice or information while you're on the road : call your home base in this country !
Optimal flexibility and freedom, but with a safety net.
For more information on these unique possibilities, send a mail.