I second the cornish game hen. My mom used to make these for our family of 5 and they make a really fantastic presentation AND they're delicious. The concept of having something like an individual "mini turkey" for each person fun and special. Like you it will be just my husband and I for Christmas. I live in the Philippines so I can't get the cornish game hens here. But if I could....that's what I would do. I may get a whole chicken and bake it, then combine it with a few family staples and one or two of his favorite dishes.
Oh and if you want to continue with the "mini" theme....here's a little trick I use on my homemade apple pie recipe. I always have leftover filling for my apple pies (family favorite, I have to make 2 every year because they go so fast). So I make a little teeny bit extra crust, then use a muffin tin to make "baby pies". The baby pies are usually served to my niece and nephew, who love getting a "whole pie" to themselves. That might be a cute way to round out the theme if you go with the game hen idea.
Otherwise....I'd stick with a small ham, baked with a honey glaze, and a few of your favorite side dishes. So what if you have some left over? Yum....ham sandwiches!!