During my 6 years with a Shakespeare company, I was known for candy. I always provided candy in rehearsals, but once we got into tech, the candy stopped since my available time to go to Costco/Walgreens stopped. So for every opening night, I would provide each actor with their own individual hand-sized bag of candy.
Granted, that sounds generic - but each bag of candy was special. During rehearsals I'd take note during the breaks of who would eat what. Some people loved snickers more, others gobbled my chocolate covered altoids, and yet one particular actor loved my ice breakers sour mints. I'd pack each bag with a small variety of candy, but mostly their individual favorites. If the cast was large, I just gave the candy in small gift bags. If the cast were smaller, and generally more close-knit, there would a small token related to the show given with the candy, or sometimes the candy would be inside the token item. At least with the actors I worked with, they always appreciated the candy.
As far as for the design team, it was not a point of mine to give them anything. And I didn't receive anything in return - except one time a costume designer for a very long-running show made cards with her renderings on them for everyone. Those were really special. I tend to write a thank you card to the director, and for my SM team, I would give them gift cards based on what I picked up during rehearsals. Complaints about gas prices and how far away the theater was, the fact that they were always stopping for Starbucks before every rehearsal and tech, or they were almost finished with this particular book in a series and that they really wanted to buy the next one.... Just like the actors and their candy, I'd give each person a gift card that fit their particular wants.