I say platinum only because I think it gives the watch a very contemporary or concept feel to it, which I think is rare for a perpetual calendar, especially a skeletonized one such as this.
Legibility is a funny issue when we discuss perpetuals, skeletonized or not. I am not sure I find this one much more difficult to read than other perpetuals with numerous tiny sub-dials and sub-sub dials with tiny numerals and writing. Let's face it, apertures are a very legible way to go when we are considering a perpetual, but perhaps apertures are less artful and simply more utilitarian -- and I am not sure that is the way to go when one wants an haute complication like the perpetual calendar. To each his own, I know. On this skeleton, the rear view is really extraordinary, and I never thought about teh references to the planisphere symbol on the backs of so many other JLCs. Nice!
The proportions of this watch also seem to me to be quite good -- not too thick when one considers it has an 8-day poerwer reserve. Such a power reserve seems to me a really important feature for a perpetual calendar (or a minute repeater) that one might not wear every day or even every few days.
And a resounding, YES, I would like to see more JLC watches finished like this one, even if it means I cannot afford them. :-(
Always, nice to see this watch, Nicolas.
Best,
respo