I was just pondering windowed mode, which I use most of the time I'm playing. It'd be really nice if there were an easier way to drop focus when windowed instead of having to hit alt+tab. Most of the more modern games will let you simply mouse in/out of the game at will whenever the cursor is up.
I'd wager they're probably using a different input library as it seems they simply use the OS supplied mouse facilities whereas NC seems to manage its own cursor facilities, so this is likely not as simple a change as it may seem up front, but it's something to consider, and of course there may be alternate methods to achieve the same end goal that are less radical!