Hi Mike,
You make a good point about student surveys. Also, at my college there is a standard survey form which does not include questions that really apply to my course. The surveys are given at the end of the course when the students are finishing their major projects so they don't devote a lot of time to filling out the surveys and when they do they are only snapshots rather than total course exposure. In short they are very little value. What I do is to give out 3x5 cards after quizzes, when projects are completed and any other time I want some candid feedback. Over the course time I may have between 3 to 5 of these feedback opportunities. I have found them extremely helpful. My students give me accurate and candid comments that really help me. I never have had a student vent during one of these feedback times. The feedback is anonymous which lets to students express themselves as they feel without any worry about the consequences.
Gary