This started as a comment, but got awfully long.
Your premise bears a lot of resemblance to the world of Avatar: The Last Airbender.
* "Each human has the ability to wield an Element corresponding to their eye colour - blue is Water, brown is Fire, green/hazel is Earth and grey is Air." While some people can't control any elements at all, those who can "bend" an element only have one of the four, and their eyes are colored accordingly. (Except for the Avatar-- more on this later.)
* "Depending on their Element, a person is given a selection of jobs by the government to choose from that are suited to it - for example, a Water may be a firefighter, and a Fire may be a blacksmith." Yes, although jobs aren't imposed by the government. This is explored more in the follow-up series The Legend of Korra, where different benders live in the same city-- firebenders use their lightning to power machinery, earthbenders construct buildings, etc.
* "An albino girl who has the rare ability to control Aether, the 'fifth element'" There is a rare fifth element, energy, although it's probably different from what you have in mind. Energybending allows a person to give or take away someone else's ability to bend.
* "A regular boy with very dark eyes, often made fun of due to his extremely weak powers." Not everyone can bend at all, so weak or no powers are common. 261
One of the main characters, <PERSON>, is a nonbender who uses mundane weapons to fight (mostly his trusty boomerang)-- though he's a contributing member of the group, his friends occasionally give him a hard time for being "normal."
* "A boy with heterochromia who has the ability to control two elements." While eye color doesn't determine bending ability (it only indicates it), one person, the Avatar, can control all the elements. His eyes have the color of his birth element, but he can learn to bend the others.
* "A girl with immense power that turns heads with a burning desire to share it with the weak." Another main character, <PERSON>, is a powerful waterbender who does everything she can to help others. The most head-turning character, though, is the blind girl <PERSON>, who is widely considered the strongest earthbender in the world.
I definitely think your series could be interesting given that your main characters defy the mold of the rest of society in different ways. If you want to avoid similarities, though, try changing your elements-- adding an extra "common" element or two, or using a different four. 722