What do you mean by hourglass style?
The 1st 2 have an issue:
Both players would have to be online at approximately the same time to guarantee the ability to make more than one move per day,
Eg. Opponents in South Africa and Japan, each spending 8pm to midnight (their local time) here, would never be able to make more than one move per day.
I looked for the post by PerfectGent about this (I think it was he who wrote it) but could not find.
So, what are some alternate ideas for time controls? Please add your own as well! Each option could have vacation and no-vacation options.
My favorite of these is the X moves in Y days. Like 20 moves in 10 days. And of course when you make your 20th moves, you get 10 more days added to your clock. This would make a system which is faster (average of half a day per move), more predictable, and less susceptible to people going on vacation.