I know how they work, I designed lightmetering systems for security cameras in a previous job. However, modern evaluative metering systems *can* work differently, they don't necessarily need an 18% reference.
Did you ever work with Ansel Adam's zonesystem?
Here is a good read... Modern evaluative metering uses similar techniques.
For example, in full evaluative mode the system can actually analyse the whole image and look for hightlights, than base the exposure on these highlights (in combination with several parameters in the rest of the measured histogram), thus making sure you use the optimal dynamic range the camera is capable of. That is very similar to what Minolta did in a crude form in their Dynax 7 series if I remember correctly (they offered a brightness distribution display). Bottom line: there *are* other ways to measure for non-18% reflective scenes.
Sunny f/16: guesswork, based on a flimsy rule of thumb. Might work in your area in circumstances you usually shoot under, but not everywhere at anytime.
Grey card: reflective (how do you determine the reading there?)
Whitepoint: What do you do with "whitepoint" where exposure is concerned?
Incident meter: agreed, the best method, beats any other method hands down - provided you can get close to your subject and take readings at different points. A little time consuming too...
Really, these methods don't offer "more control", that's just a state of mind. You have full control over exposure in both, manual and (half-) automatic modes, you just need to know what you're measuring and how to do it correctly (but that goes for incident reading too...
).
Bottom line: use whatever you feel most comfortable with in a given situation - if that is manual mode after having measured using incident reading or any other effective method, great. But do not wipe other techniques off the table - they can be at least as effective - if you know their limitations.