I must say that getting my creative juices to produce [size=9px](hmm, somehow I wrote that as procedure first :?)[/size] an interesting gameplan is an entire challenge to itself. Especially when it has to involve such odd game characters.
So far the 'juice' hasn't really done any good for me though; the ultimate gameidea is still far far away.

I have been keeping an eye out on the gamedev forum to see if the competition out there is giving some pointers, but somehow the main point of discussion seems to be the rules. Save a few 'space pirates' and 'ninja robots' (pretty much what we've seen here too) and an occasional 'I'm gonna do a 2d platformer'', they're not giving that much away.

Too see what we all may be up against, I thought it would be a good idea to post this link http://www.gamedev.net/community/contest/.
It has all previous contests listed, including screenhots and files so you can have a peek of the competitions capabilities. To my surprise gamedev's last 4 elements compo had only 44 entries, ranging from guess the number to 3D games. (The winner is quite fun though, definitely worth the download).

The plan to create a RTS game as an entry is IMO quite amazing. My hat off if you can actually pull it off.
But if I may, the gametype itself is already difficult, I wouldn't add more problems to that by choosing all four characters for you game. Rules clearly state that you're okay with just 2 of the four elements.

Also the suggestion to create a world for each race sounds like a lot of work just to get a story. I'd keep it simple: 1 prefered element on the left, second prefered element on the right. Build a base and go for it.
Main problems as far I can tell here is the AI and balancing. Well that and graphics if you don't like using someone elses.

cairnswm: I like your idea of time based unit creation. Reminds me a bit of Z:steel soldiers where after an x amount of time a new soldier was created. Hmmm, hey! That could actually be something....

Anyway, its time to get a few ZZzz myself so I'm off to bed. Hope to see some news thoughts in the morning though