I don't paint cards for Christmas,but,I have a friend whom I have known for 50 years,since we were little kids in school. He and his family live 1000km(600 miles) away. Every birthday of mine he sends me a store bought card,but on his birthday I send him a small painting pertaining to his life,eg his first car or his house.
I paint them on a small canvas panel,write his name & address on the back,along with a stamp & put into the post,exactly like a postcard,no envelope.
His wife tells me he has kept every one of them & shows all who come by. His cards to me are read & tossed out (hope he's not an eHangarer)