We thought this location was perfect and wouldn't change a thing. It's about a 15 minute walk to the red light district, which means it's quiet when you want to sleep but plenty of activity is nearby when you want it.
There are a lot of excellent places for food within easy walking distance, as are the Van Gogh Museum, Anne Frank House and many other attractions.
There's no real view to speak of and no balcony, but there's so much to do in Amsterdam that we hardly think it's worth paying more for those features when you'll be out doing other stuff 90% of your time in Amsterdam.
The flat itself is incredibly clean and comfortable, with a HUGE bath tub for couples baths. We were met at the door within 2 minutes of our arrival and they had a handy map in the flat and offered lots of suggestions for shopping, food and entertainment. We never met Kate, but the gentleman who checked us in (so sorry we can't remember his name) was very friendly and helpful.
Overall this was a top-notch experience and we would gladly stay here again.