I have been living in Copenhagen for 5 years, and my British family came to visit this Christmas, so we booked Lisa's cosy apartment.
The stay was an absolute joy! The apartment is in the central part of CPH, right next to the lakes (perfect for a stroll), and alongside the Botanical Gardens, the food market (Torvehallerne), the national art gallery (SMK), and more.
And then there's the apartment. I have never quite seen such a hygge apartment in Copenhagen! Lisa's home is charming, well furnished and cosy. It was perfect for my parents (60+), my sister, my niece and nephew (lots of kids' toys), and myself. It was clean, the beds are comfy, and the balcony is a perfect spot for some morning reflection with a coffee.
The one thing I would flag is that, there is another apartment right above this high-ground floor spot, with a family. The two youngish kids can be a little noisy in the morning (not too early), but enough that I wouldn't recommend the apartment for anyone that wants to have a lazy morning and wake up late.
All that said, this really is the perfect family apartment in Copenhagen. You'll have a great stay here.