If he's a real watch lover, don't go for the jeweler's brands (ie, Cartier, Tiffany, etc.).
Try to find something from Patek, IWC, Jaeger LeCoultre, BlancPain, Vacheron. I feel like Omega and Breitling are on a level below. For $6k, you can get a beautiful IWC Portuguese, check them out.
Also, if he's more into traditional styles, he won't be a fan of Panerai.
I don't think Jaeger gets enough love.
http://personalisation.jaeger-lecoultre.com/#/accueil
For a special birthday, you can get a special engaving if you get a Reverso. Mr. Bitty has a Master Control Ultra Thin I got him for his 40th. It has appreciated significantly in value.
Agreeeee! But then again, I'm biased - I just bought a Reverso Duetto Duo, so no blank slate to play with. Have you seen this guy?? http://www.jcengraver.com/
Also, last year the Reverso was ranked second in iconic watches after the Rolex Submariner.
Yes, my Lady Reverso watch was engraved by him.
That is stunning!! I love the design! And you're so right, it seems that only men get this fun hidden stuff done behind their watches. I think it's time we bite on to that tradition.
Here are pics of my unadorned baby.