I would definately invest in an Argyll/Crail/Braemar style jacket.

They're amazingly versatile. I've seen them worn with a black crewneck shirt for a Hollywood-like semi-casual look, a turtleneck, with an oxford button-down shirt both with and without tie, with dress shirt and long necktie to match in with men in suits, with Churchill collar shirt and black bowtie to match in with men in tuxedos.

They can be dressed up with shoulder plaid as seen in my avatar (though technically speaking such a plaid should be worn with one of the more formal Highland jacket styles).

Anyhow, with an Argyll jacket you'll be perfect for any of the appearances you'll be making with your wonderful wife! Congratulations to you all!

PS black kilt hose are becoming quite the fashion recently and will give a nice dignified formal look. I would avoid cream/offwhite kilt hose myself.