I don't think anyone should be expecting to get anything too bid from OPC.
You may get a decorated cabin, or possibly a bottle of wine...if you're already a very established player.
If you play slots the machines track your play, and collect points which you can cash in at the end of the cruise for logo stuff or cash back.
It takes ALOT of play to get anywhere.... but if you spend alot of time gambling, something is better than nothing I guess
For table players... if you are high limit players and make sure the pit supervisors notice your play, you'll get some free drinks while playing. Other than that... a bag of logo "junk" at the end of the cruise.
If you're a BIG player... you may get a bottle of wine sent to you in the dining room.... and maybe, maybe an offer to send you to the alternate restaurant for dinner.
When OPC first began they had a fairly decent cash back program for table players too, but that went away a couple of years back.
I'm presently working on an article about cruise ship casinos/gambling and high roller programs, and OPC tells me that their "members" are 70% slot players, and 30% table players.
It takes much longer times of play to earn points at the tables, than on the slots. That's because you can lose money much more quickly on the slots. Table games are better odds, so theoretically it takes longer to lose.