It is fair to say that piano technicians DO know how to tune with
key color and that Victorian temperaments enable them to do so.
One of the best is the Moore temperament which permits key color
and will slide by as equal if you don't talk about it. But the
pianos sure do sound better!
Deviation in cents from equal
C 2.50 Moore & Moore
For a little more spice:
C 5 "Broadwood Best" from Avery list
Chopin preludes played on this temperament are incredible.
Try it, you'll like it!