I have multiple monitors, and with Quicksilver and Magic Mouse gestures I open applications without using the dock more often than with it. Is there a way to have these application windows appear on the monitor that currently has the mouse cursor? An added bonus would be the ability to have Finder open a new window if there isn't one on the current monitor, even if there is one on the other monitor.
I think Mr. Siracusa has railed against the lack of consistency or flexibility that leads to a situation like this, and I don't have a "you can modify this plist and presto!" answer either, but I saw this and thought of your plight: cordlessdog.com/stay/
It may not be what you need, but it could be a step in the right direction, which I heard of here: http://twitter.com/wilsonminer/status/20750686482
I've never come across anything that would tick all those boxes unfortunately. I simply don't think the OS supports that at the moment. Sorry I can't offer more help.