All fruits and vegetables will have many health benefits, including fiber, vitamins, minerals, antioxidants, and high water content. The carbohydrates found in things like fruit are not what causes obesity since it is a carbohydrate source from a whole food. The bottom line is that nobody becomes obese from eating whole foods like fruits and vegetables. Fruits such as bananas are actually lower on the glycemic index than most breads and pastas. Processed carbohydrates, on the other hand, have an imbalance of fructose to glucose and are often completely unnatural, and these refined carbohydrate sources are what cause health problems.
I think any fruit or vegetable should be eaten in abundance, unless it's a high-fat vegetable or fruit such as avocado. Also, leafy green vegetables will have a higher vitamin and mineral content than vegetables like potatoes. The bottom line is that all fruits and vegetables are good for you, but some are better than others in different ways.