I think a cab may run you around €35. Per your hotel's website the shuttle stops running at midnight so you'd have to catch a train shortly after 11:00 in order to make it on time. You may want to consider a hotel closer to centrum so you'll have more time to explore. There is a shuttle service, Connexxion (formerly called KLM), that will get you from Schiphol to town for around €20 r/t. or you can take the train to CS and ride the trams. Since your flight is intra-Europe I imagine you would only need to get to the airport an hour early. If you stayed in the city centre and are an early riser that would give you a little more time to look around in the a.m. There is an Amsterdam forum, Channels.nl, that has a very detailed database of restaurant and hotel reviews as well as a red light and coffeeshop forum. It's mainly frequented by the dope smokers who go to AMS for that but a wide range of people post there including Flyertalk legend Doc.