Regarding the discussion about the reformation of the time limits I want to suggest something that I saw at another server:

There are only four possibilities to choose:

1.Blitzgame: 10 moves in five days
2.Fast game :10 moves in 10 days
3.Regular game: 10 moves in 20 days
4.Slow game: 10 moves in 30 days

With weekends, vacation and perhaps with time accumulating the last suggestion seems to be more than enough for slow player too!