Affluent Areas of Shinjuku

Are there any particular neighbourhoods within Shinjuku that are known for being upper-class, trendy and affluent like Daikanyama?

Nishi-Shinjuku has a good number of relatively expensive high-rise residential buildings, and a lot of commercial activity, and I guess there are some trendy sections. Shinjuku-ku also has affluent low-rise neighborhoods that are almost entirely residential, so I guess you wouldn't call them trendy. Probably Kagurazaka is the closest combination of affluent and trendy, with far more upscale dining options than Daikanyama.

I don't know how useful it is to talk about wards though - they don't really correspond to neighborhoods (e.g. a lot of the Shinjuku Station area is actually in Shibuya-ku), and a lot of recognizable neighborhoods are split between different wards.