What we did on our last cruise was ask some of our servers (didn't have the kids, so the kids club counselors were a non issue) what were some of their favorite things that they just couldn't get on the ship. Then, in one of the ports, we took a bit of our own shopping time, and went and got those items. They were VERY well recieved. Our server, Antonio from Mexico, liked gummi bears. We gave him 3 bags on the last night, and the next morning, he said that he had already eaten a whole bag. Our assistant server, Pema from India, missed magazines she couldn't get onboard, particularly cosmo. So, we gave her a selection of magazines. Things that aren't particularly monetarilly expensive, but really meant a lot to the servers.
I think one of the things I'm going to do for the kids club counselors on our next cruise is homemade goodies of some sort that they can put in their break room (if such a thing exists). I know they dont' get "home cooked" food very often. Being that we are cruising at Christmas time, I always have LOTS of goodies ( I can't help it...Christmas baking has been programmed into me from birth).
Just some ideas.