Well, as father of the bride, you could always go with a jabot.

It's very formal, but it looks great. My father-in-law sported one for my son's wedding this July. He really looked like the patriarch of the family.

http://new.photos.yahoo.com/frjohnpe...03254283411/21

For my part, I have such a long beard that I didn't even wear a tie, and no one could tell.

http://new.photos.yahoo.com/frjohnpe...803254245606/5

Here were all the kilted gents in one pic. Alot of variety, and the party is formal.

http://new.photos.yahoo.com/frjohnpe...03254200329/32

Congratulations by the way. I don't think you can go wrong.