Are the majority of the guests staying in Seattle?
Palisade is nice, and a good location, they do a good job. I love their view, but in January, it will be dark, dark, dark, so, personally I think I would consider other locations that are more central to downtown or to where your wedding party is staying.
Tulio is warm, inviting and wonderful. I always enjoy a dinner at Tulio during the winter months just for that reason. It's smallish restaurant, and the private dining area would suit your group. The food is delicious and it's not "stuffy" or old school in any way.
Dahlia Lounge (Tom Douglas) is a Seattle classic, in a good way. Their private dining room would suit your group well. I like Dahlia for out-of-town guests because of their emphasis on local, organic Northwest preparations. You won't be disappointed. Plus you can have TD'd coconut cream pie for dessert. It's located right in the heart of downtown.
Right at the Pike Place Market, you might enjoy Steelhead Diner. They have a private dining room that is just the right size for your group.
Also right in the market, and something perhaps a little different, outside the box, you might consider renting the Tasting Room Seattle. It's a wine co-op, and a nice space for a smaller group. They can coordinate food options.
Another option, and one of my favorites is Serafina and it's sister Cicchetti. Located near Lake Union, it's more of a neighborhood restaurant. Warm, wonderful dining. Fabulous food. Typically music on the weekends, if guests want to linger after your event.
Hope that helps!