I have an idea to make your Giant card more personal....do a photo collage on the inside of you and you and him together. That way if it is allowed he can tack it on the wall and he can show it off to everyone. Guys love to show off LOL
As far as what to buy him...I don't know him so couldn't make a guess. My husband is happy with a new x-box game or a new pocket knife for his collection.