I have an idea for passwording missions that involves adding one "Password" button to the mission viewer and editor. How this would work is:
You select the mission viewer from the clipboard. It shows no missions.
You click the password button and a box comes up asking if you have a password. You type in the password and hit OK.
Aces High checks if there is a mission with the password that you typed in. If it finds one, it will become visible on the viewer and you can join it normally. If you don't join the passworded mission it will disappear shortly.
This password button is also in the editor so you can set it easily.
I believe this is superior to the method where a mission appears as "locked" and you need to enter the password to join it because the mission will not even show up unless you know the password.
Here's another suggestion for the mission editor: Make the launch field default to the field you're currently at instead of 1. This would eliminate the pain in the rear of scrolling through the list of fields.