Personally, I'm not for a million af points on the screen. I want a nice selection I can use different zone settings, covering much of the area as possible.. but I don't need hundreds. Love to see where I could select MY wanted AF points, in any combo, and then roll thru them on a dial. Like my own custom AF layout. THAT would be exceptional and fast. There are times I need the camera to do all the af for me, but many times I know where I want that point of focus at. Most of the time I don't need or want a zillion, and they get in the way when there are too many.. being able to select a sub set, and roll thru them is my ideal camera.
The Sony's have such a high number of AF points because the AF points span the entire frame, and because they provide a greater density of AF points when tracking, and thus, are able to make smaller, more precise movements when tracking
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That said, in real use, you're usually designating AF zones or movable AF points that you can toggle to different sizes. A small point is limited to 1 PDAF point, medium is a cluster of points, and large is a larger cluster of points. Personally since I shoot primarily portraiture, I don't mess with AF points at all and rely primarily on continuous eye focus and face detect. When not shooting portraiture, I use lock-on focus to acquire the subject via the center-point....and let the AF system lock onto my subject as I frame the shot. As these AF systems grow ever more intelligent, toggling through AF points is growing ever more antiquated.


