Each game should have a setting for how many moves a player is allowed until they have to wait for everyone else to make at least one move.

This might prevent the game from being "spammed" by those with way more time on their hand than others.

For example, I work a 12 hour shift, and by the time I come home, a lot has happened in the games I play in. Every twenty minutes, I get an email saying somebody has made another move. This might go on to a point where my character can't fit in anymore, is simply just "standing around", or other continuity issues.

I believe a move-limit set by the narrator would help preventing those with more time on their hands to spam the scene and sail off without the people that can't be online 24/7.

Of course, the narrator should be able to adjust this on-the-fly, opening up moves for players already moved if needed (like if a player is absent for too long, or not needed in this scene, or whatever). Likewise, a player should have the option to skip their moves and allowing others to continue on.