What happens when you hook a pressure plate or a lever up to a door? It doesn't seem to offer any options for the link.
What I'd like to see is the ability to choose how the door will be affected when the link is being installed. For instance, when you're installing a link from a pressure plate to a door, you could have the following options:
* Pressure plate opens door.
* Pressure plate closes door.
* Pressure plate cycles door.
When something 'closes' a door, it sets it to tightly-shut and impassible. The cycling a door would open it if it's closed, or close it when it's open.
For a lever, the options would be:
* Lever opens door.
* Lever closes door.
* Lever cycles door.
* Door is open/closed based on lever.
* Door is closed/open based on lever.
(The last two would set the door to the appropate state based on the lever's position--open when it's on the left and closed on the right, or vice-versa. Nothing happens to doors that are already in the correct state when the lever is pulled.)
Why all these options? First, always setting a door to open or closed could be useful for traps. You could have a pressure plate slam every exit from a room closed and flood it, or open a door with something nasty behind it, or both.
For levers, the option to have doors go to a specific state matching the lever's position lets you have complicated door-arrays while still being certain that they'll all go to the right place when you pull the lever, even if some goofball has been opening or closing them.