Some of the basics are:
- When the lid is closed, the computer must suspend
- Just because I have music playing, my laptop must not refuse to suspend when I ask it to
- When the user changes the brightness, he doesn't appreciate if the computer turns it right back down again (or vice-versa up again)
There are only a few situations where I can see not wanting to suspend on lid close:
- when docked
- when using an external display (watching a movie on a TV)
- and, of course, when explicitly asked not to
- The cursor should not blink (GTK+ has a cursor-blink-timeout setting for stopping any cursor blinking after a configurable time without user interaction)
- Suspend to do a simultaneous (transparent) Hibernate (to cope with battery death).
- Automatically wake up after 30 minutes on suspend and immediately power off the machine (leaving the hiberated image).
- Laptops: waste no more power on "AC" than on battery... the "AC" can be coming from a battery bank and inverter
- Try to work out a sensible protocol for when unneeded BT/WLAN/GPRS radios can be powered off (though this rubs against "just works" Bluetooth/Wifi association magic).