Lol this is a dangerous question. Scientific studies have shown that people with "symetrical" faces (Are generally considered attractive or beautiful) are much more likely to leave their partner for someone they consider more beautiful. They tend to always subconsciously search for a more attractive partner. Example: Someone like Eric Benet could cheat on Halle Berry, despite how pretty she is. Or Brad Pitt cheating on Jennifer Aniston. It's almost in the DNA.
I can't imagine any face I'd rather see than his. He wouldn't be the man I love, and that's about as attractive as anyone can get. His face symbolizes 'him' to me. I haven't the slightest desire for him to look any other way.
This is a very interesting question you ask. Many people have preferences but you don't always fall in love with a person that will have those features. For example Zac Efron has the most beautiful eyes in my opinion but if a brown eyed guy is who I love with then I wouldn't care. I couldn't imagine trying to change a person