A bit of Etymology
"プラスアルファ" comes from Japanese baseball players' misunderstanding X as α when American baseball players marked X in the second half of 9th inning for the record. If the bottom team had more scores than the top team when they finished in the first-half inning of the 9th inning, they don't have to play in the bottom inning. So, they could have been able to score more if they had the bottom inning. Hence, they marked top:5 - bottom: 7 + X for the record.
A bit of Analysis of Meaning and Translation
As I mentioned above, "プラスアルファ" implies adding something onto quantity or quality. It is normally used when you need/can add something more than the expectation.
"ステータス" is difficult to define. Having an imported car, wearing Armani or ROLEX would have been "ステータス" 30 years ago, but I guess fewer people care about having that stuff in Japan. The definition of "ステータス" has been changing quickly. So "価値観" does. Businessman and Artist would have different images for "価値観".
All in all, it seems to me this sentence wants to encourage us to bring synergy to Tokyo through fashion, art, lifestyle, and diversity.