in case your posting is not
an early April Fools Joke, I'm afraid you will have to abandon your idea of holding a nice BBQ onboard. You will neither be allowed to bring a pig onboard any cruise ship nor will you be allowed to handle with any kind of open fire on your balcony that goes beyond smoking a cigarette etc.
Also, the cruise line will more than likely confiscate any "kegs of beer" upon embarkation and will hand them back to you on disembarkation day. And no, you won't be able to "party with the crew" as they will get fired when caught in a passenger space.
So, if your posting is indeed serious, I would suggest to simply drop the idea of going on a cruise.