Understanding the structure, '又什么...' and '又没什么...'
又什么麻烦/ is a wrong expression. The correct one is 有什么麻烦, which could be either a rhetorical or a generic question. The normal expression is 又有什么... and in some cases  有 can be omitted, but you should be careful. In your example, 又有什么不满意 and 又有什么麻烦， 有 should not be omitted. 

Well, in 又没(有)什么麻烦, 又 is more like the English word anyway in my opinion. So, 又没(有)什么麻烦 could be interpreted as there isn't any trouble, anyways.

Compare 又没有什么麻烦 and 又有什么麻烦. The latter is a rhetorical device as you said. The former is a normal negative sentence.  Both denote the same underlying meaning, but with a bit different tones, which are the same as the correspondent English sentences. 

An interesting phrase I also want to add here is 又什么事，which is short for 又有什么事. In this context, 有 can be omitted. So, I suggest you add 有 all the time unless you know for sure it's right to drop it in your context.