Sounds good, though I'll see your point about possible abuse and raise it to say that sooner or later it's inevitable that someone will try to abuse it.One interesting approach is to implement something one of my groups calls "fate of the party." Absent PCs continue to play, and may even act recklessly if the group deems it to be in-character. However, to avoid players coming back to discover that their character died, the PC cannot die unless the party wipes. The gain just enough plot armor to survive even if KO'd.
It's obviously open to abuse, but with the right group it can be a have-your-cake-and-eat-it-too solution.
We generally have it that if you're not there your character is just as (but no more than usual) susceptible to death or other Bad Things as it'd be if you were there; dice can be a beast sometimes, and this is accepted by all involved. That said, you're also just as susceptible to Good Things happening should they arise.
That, and in these days of instant communication via text message it's rare that if some truly earth-shattering decision needs to be made we can't at least try to get a few shreds of input from the missing player.