yogsloth: For pacing - think of the difference between Game 30, where a Day lasted five days, vs. Game 27 where a Day lasted two weeks.
For posting frequency - this is harder to quantify. Somebody mathier than me (wyrm, bler, agent) could probably do a regression analysis on player post/day and figure out what a general rule of thumb would be on posting expecations. Ulitmately, common sense would have to prevail. If you want to post once per day or twenty times per day, you can probably sort yourself pretty easily. If you're in-between, just use a common sense judgement.
To be honest, I think a different solution might be required... thought I don't know how well it would work in practice.
I was thinking a minimum and maximum number of posts per game day. If you fail to reach the minimum or go over the maximum you get penalised (similar to RWarehall's editing punishments but also things like chances of your Night Action failing or something)
That way everyone is forced to think more about their input, there is never quite so much to catch up on, so if your away for a few days you don't become stuck in a catch up loop days responding to things that happened days ago (I seem to recall this has happened to HijacK at least in one game) but no one can skate by not saying anything...
It may not actually work, but the fact is you clearly can't force everyone to post more or run days that last 24 hours and hope everyone will be able to contribute...