We had such an amazing stay when visiting Prague. We took advantage of this space and invited my family to stay with us (including my grandma). The place was huge, had an amazing river view and (castle + Petrin tower) easy access (elevator). The suite is truly luxurious with 2 awesome bathrooms (one shower, one bathtub), smart TV (Netflix, etc.) in the living room, comfy couch, two balconies and plenty of storage space. Checking is contactless and you only need a key code for the building and the apartment.
If you're looking for a spot close to all the tourist attractions, you won't find any better. That being said the area gets really busy in the summer so if you're looking for something quieter you'll probably be better off with Vinoharady or Letna neighbourhoods. Just a few steps outside you're at Naplavka which is a beautiful river promenade with many bars and boat restaurants. Dancing house is also just steps away. Make sure to make a reservation ahead of time since these restaurants get pretty busy during the season. Another fun activity we managed to do is to rent paddle boats on the nearby island and spend an hour floating on Vltava with its gorgeous views. Finally Charles Bridge, National theatre and other sights are just a few minutes away - go see them all!