The Celestial is truely and exceptional watch, a unique watch.
My choice would be the 5102, as I like YG for it's various moods, depending on the light.
YG creates a very particular shine as well as a dull glance that makes the material look like as if it would nearly "flow".
IMHO the Celestial is with 43 mm not a formal watch, also due to the design.
It is a very, very impressive, but still not an ostentatious watch.
The perfect bow tie and formal watch is: 5120 G.
The 5120 G is a perfect watch for ANY occasion ( reception as well as casual ) and also a very complete watch with a screwed back case, an iconic caliber 240, a perfect case / movement ratio ...
The occasion itself is the honour and understatement is the call of the day for formal gatherings.
Regards
Moritz