Cruise fashion necessities, What do I bring?! Options

[megggnasty]

I'm going on a cruise for 7 days over the Christmas break (which includes New Years Eve, yay!) and I'm not really sure what to pack... as I'm limitted to one suitcase and I ALWAYS pack more than I actually wear. There are fancy restaurants and night clubs and I plan on staying up pretty much all night, every night. But I'm lost with what I should bring.

[moorepocket]

for guys:
shirts (button-down long/short sleves) and polos.
pants, khaki, or dark navy jeans (no holes, or faded)
blazers
leather flip flops, non-atlethic sneakers, or dress shoes

for girls:
blouses and polos.
pants, khaki, or dark navy jeans (no holes, or faded)
skirts (think pencil-skirt, or A-line)
(cropped) jackets
sandals/heels

[megggnasty]

for girls:
blouses and polos.
pants, khaki, or dark navy jeans (no holes, or faded)
skirts (think pencil-skirt, or A-line)
(cropped) jackets
sandals/heels

That's exactly the type of guidance I need. Thanks! :)

I'm going on an Eastern Caribbean cruise, so I won't be needing any windbreakers.. it's going to be balmy and beautiful! But I want to be able to look chic, because it is a cruise and I'm pretty sure we'll be expected to look put together. I absolutely hate walking around in PJs or sweats (unless I'm jogging or going to a work out room/yoga, etc.) It's my biggest pet peeve... you never know who you're going to meet.

What about dresses/club attire? How many would be a suitable amount to bring? I hate wearing one thing more than once in a week, which makes it more difficult. I may have to deal with it, haha.