The elements idea reminds me of Captain Planet (which was an awesome show, so not slamming the idea at all!) LOL, but it also reminds me of the album art for Millennium, which is still one of my favorite Bsb photoshoots. Though when I looked back at which element you chose for which guy, it made me think more of the Incomplete video... Brian with water, Nick with fire, etc., as opposed to Brian = air, Nick = water, Howie = fire, etc. Is that where you got the idea?
The elements have been connected to fantasy since ancient Greek and Roman times, when they believed there was a god who controlled each of them, so it makes sense. It's a classic idea. I wouldn't throw it out just because it's been done before. You can always take an old idea and make it new again, especially in this fandom when so few stories like that are being written currently.