I'm really not sure. Maybe our esteemed research colleague Mr Crunch can help out. It wouldn't surprise me if the bell diameter on the 22" is always the same as the 20" because they use the same die when they press it in. Although they could be different. I don't know. And I don't know if the Ride and Medium would have different bell sizes.
I wouldn't expect any variation in the lathing. All the 602 lathing I've seen is consistent. The only exceptions to the larger tonal groove style you've got there on both of yours are a few specific models which all have very fine lathing: flat rides, sound edge hats, and a few Seven Sound Set or Morello models.
Back to bells. Once upon a time, I did notice that the bell diameter on my 20" Sound Creation Medium Dark Ride (4.5" ) was distinctly smaller than the bell on my 20" 602 pre serial (5"), leading me to think that a smaller bell is part of making a Dark ride have fewer high frequencies (despite being heavier). 20" Dark Rides also have the 4.5" diameter bell (but we need some more data to recheck this).
The 22" Dark Rides have 5" bells so larger diameter than the 20" Dark Rides (4.5"), from the few I've got measurements for. I think (but am not sure! Need more info!) the 22" 602s also have a 5" bell.
So all we know so far is that sometimes Paiste use a different bell diameter for different (20" vs 22") cymbal diameters in the Sound Creation series. But it seems that both the Sound Creation 22" and the 602 22" have 5" diameter bells which suggests it isn't the parameter they vary to get the 22" Dark to be darker than the 22" 602. Just to be complete, the big bell prize goes to the 22" Sound Creation Bell Ride at 5.5". As you might expect.
So the picture is complex and needs more people who have 22" cymbals to measure the bell diameter. This is an older project which got stalled before I had enough data, and the previous writeup got lost somewhere in my records (or distributed across several places). Embarrassing, but there it is.
So maybe the MEDIUM RIDE in the 602 series will have a larger diameter bell than the MEDIUM in order to get that additional silvery ping. More high frequency tones is one of the outcomes of a larger diameter bell. But there are other sonic parameters which might be the ones Paiste adjust. There is bell height (another way to get a "larger" bell, there is taper (perhaps more to do with crashability), and there is the amount of bow (which shows how much tension the cymbal is holding). Many parameters which all interact. Or it might be just weight.
Calling CaptainCrunch. Do you have any bell diameter measurements to add in here?
And Black Label, what bell diameter have you got on those two? My guess is that the diameter of both bells will be 5". They look the same in your photos.