From working on ships, I can answer most of your questions, although feel free to call me to get the complete rundown.
1) What types of gigs are there?
There is the show band - this is what I played. Show band musicians are usually hired through the company directly. They play the main stage shows such as the Vegas and Broadway style shows as well as variety acts and jazz sets. For this position, you will need to sightread - you will most likely be sightreading live shows the first night. There is little rehearsals. You will also need to know a large range of styles and be comfortable playing with a click.
2) What is the schedule like and what free time do you have?
You will probably be playing some type of show every day. Some days you may only have 2 production shows - one hour each. Other days, you may need to do some other shows. Usually 4 hrs. of playing per day maximum.
3) What is the pay?
The pay varies, but since room and food is free, you will be able to save most of the money.
4) Audition tips
Most auditions are over the phone. They will email you the charts. You will print them out as soon as they are emailed and sightread them down. You will also be asked to play a number of different styles. For an idea of what the charts are like, check out Steve Houghten's Drum Chart Reading Anthology
http://www.steveweissmusic.com/product/1215/drum-set-methods-cd
5) What are good drummers and bands to listen to?
Everything - from big band to latin to hip hop, R&B, country, tangos, bossa novas, Broadway show tunes, etc...
6) Anything else worth mentioning
As I mentioned, call me for more information
Jeff