12 hour turns have been suggested in the past. If you would like to see this option possibly implemented post your support in
this suggestion thread. Thus far the suggestion has not had much traction as many users frequently experience periods of time where they are away from the computer, or otherwise unable to take their turns, for greater than 12 hours.
If you want to be able play faster the best way is to upgrade to
Premium Membership. This allows you play more than 4 simultaneous games, thus you will have more turns to take, and to play speed games with round times of 1-5 minutes.
Another option is to head to the Callouts tab in
Live Chat. There you can look for players interesting in playing a real time game.