My Cosmonaute is quite honestly the most (imho) beautiful timepiece I have ever had the pleasure to own. Makes a Rolex or Omega look mundane (again, imho).
Overkill for bimbling about in a 172? Absolutely, but certainly gets the ladies attention at the bar!
It also has the brightest luminescence on the hands that I have ever seen - in a dark room, you can find a light switch by it, it will illuminate a patch on the wall at a distance of around 4-5 inches. Impressive (although I'm probably being exposed to untold radiation levels) -althought the wife can spot me trying to sneak in to bed after a night out with the lads thanks to the beacon effect!.
As regards a (new) custom watch and features you'd want added it depends.
If you're using the watch for actual flying - then 2 hands which tell the time, and possibly something which shows UTC. That's pretty much all you need.
If you're using the watch as jewellery, then you can add the (never used) slide rule etc.
I personally prefer round watches unless they're digital, and metal, unless they're part of the design - plastic always looks cheap which isn't any use for the 2nd option
Ultimately - you don't need anything other than a basic clock as a pilot watch.
(Although the Breitling Co-pilot looks great, but only fits the Aerospaces).