1 & 3 are your best bets for FP use, and it depends upon what software, etc., you are using as to what makes sense. #1 is the technically accurate method, but suffers at low stimulus levels from a lack of photons to make the measurements work. #3 ignores the screen, so that can be especially irritating for folks using non-matte white screens. I hate to say it, but there really is not a "good" answer that works for all people in all cases. My guess is that most professionals use a screen offset and measure direct.
Color accuracy evangelist and CalMAN insider