I actually think Gaia is the RIGHT side of the river for seeing Porto for the first time! This flat is in the perfect position for a stroll down to the best view in the city at the Jardim Do Morro where a chilled vibe waits for the sunset over the mouth of the Duoro.
The apartment is spacious, super clean and comfortable. There's a Metro stop right outside, a supermarket a block away and a bakery selling pastel de nata right below for breakfast.
Thoroughly recommended.