Which adjective is the most suitable to express "rich" for a person?
年轻中国女人很___。
  
  为什么华人那么___?


In your context, among those words you listed,  only 富 is appropriate. 富 means 富有；有钱；having lots of money. 

肥 can also fit, but it will mean fat, which would be an insult. 

阔 might be also ok, meaning "having lots of money or able to spend lots of money". But it's not that common as 富 or 有钱.

The rest 丰盛，浓郁，富足 are usually used to describe things, conditions and etc.