When thinking about competition I think there are two sorts of pepole.
Those who prefer short competitions, as it alows them to quickly output an idea without the need to worry to much about details.
And there are those who would like to have bigger time frame either due the fact that their knowledge might not be good enough to quickly turn some idea into code or due the fact that many pepole are quite limited with their time.

So after giving it some thought next thing came to me:
Where does it say that we need to have only one competition running at one time?
Why not runn more than one competition? Why not have anual competition with longer timeframe and a series of mini competitions?
And if we chose theme for mini competitions right finishing them might help pepole finish anual competition aswel. This might be a win-win solution for most of the pepole.