Hello Client,
According to your requirements,
I have created a relaxing space beside the stairs with a tv cabinet in front. There is also a shelf for plants and decorative items.
In the corner which is in front of the stairs, I have placed a music system to enjoy music while playing and there is a rug and enough space for kids to play.
On the opposite side of it, I have placed the arcade game and the stick hold leaving enough space to play comfortably. Rest walls are covered with decorative picture frames. You can place your favorite picture in those frame sizes. They will look beautiful.
I have also used lights in the false ceiling and behind the picture farmes to light up the room.

Lists of plants you can place inside:
1. ZZ Plant
2. Chinese Evergreen
3. Cast Iron Plant
4. Monstera
5. Staghorn Fern
Hope you like it and your wife loves this gift.
Thank you