Choose something that is representative of you. Over the years I have given a variety of thank you / Christmas gifts. For past clients who still reside here I provided fresh evergreen wreaths with a hand written thank you note (delivered in person). Other times I made shortbread cookies with a hand written thank you note (delivered in person). For current clients I sent (via snail mail) a Christmas Card with a hand written note. And it was always that hand written thank you note that impressed them.
How did I do it? I stayed up night after night going over my lists, writing the notes, ordering wreaths, making cookies, sealing envelopes. And it was worth every second I spent.
So...you have time. What are you going do for the people who put their trust and faith in you? A hand written thank you / Christmas note is the least you can do to say thank you!