On paper each country in the kingdom is suppose to be equal. However, European Netherlands has about 98% of both territory and population of the kingdom, not to mention the cultural meaning of being the Netherlands.
There are uniqueness to each country, though. European Netherlands uses the Euro as the primary currency but Aruba has the florin and the Netherlands Antilles uses the gulden. European Netherlands official language is Dutch but Frisian, Dutch Lox Saxon, and Limburgish are also recognized. Aruba's official languages are Dutch and a creole language Papiamento while English and Spanish are also known to many. Netherlands Antilles recognizes Dutch, Papiamento, and English officially.