These ideas covered some good ground, with the different types of tests showing different advantages and disadvantages. Writing that great question is satisfying and ultimately helps the student!
One thing that should not be forgotten is the readability of format, not just content. That is, using white space effectively, having proper indenting, readable font size and type, and not crowding the margins. These are often forgotten and can result in just as much frustration as a question that's worded poorly.
