All kidding aside, the size of the drums has a lot to do with transporting and sound. I think Rogers issued a lot of 20,12,16 kits because the tonal range from 12 tom to 16 inch tom is wider and therefore a bit more versatile. The 20" bass was a bit more space conscious but had pretty good punch. The smallest sizes were associated with jazz for dealing with transportation in cabs and the limited stages of clubs in the years after the big band and dance halls had faded due to the lack of funds to support them.
Overall though, the larger sizes provide a bigger sound and project more easily in larger venues.
I always dragged out a smaller kit whenever possible because they are lighter, easier to reach around and overall more comfortable for the body size I have. I used them regularly for smaller clubs. They also tended to fit better in my smaller cars, like the MINI I currently own. But if I played a larger hall, I used a 22,13,16 because I didn't have to hit them as hard to match the volume of the rest of the band. I'd have to stick the floor tom on the passenger seat or something instead of in the back with the rest of the stuff when I went to the larger sizes, but you did what you had to do.
I also like to use vintage stands because they look nice and are lighter and induce less back strain. However, I had a couple of gigs this summer where the modern stands would have been handy because the wind was too strong for the Rogers swan-legged stands I had with me. I had to have a cement block on one of them and completely abandon the other crash cymbal.
(Then there is still the matter of the lopsided look of 20,12,16. Walking)