I have booked 3 cruises with VTG; they were wonderful. Documents received timeley & VTG even "matched" competitors prices. For example, Expedia or Orbitz offered an incentive of credit card rewards & VTG matched the amount but gave it to us as a shipboard credit. They are a very reputable company.
Princess is great. You can go on line & view your cabin location and book tours. I would recommend you consider your dinner assignment. I liked alternative dining so when we had excursions; we could alter the dining time. I recommend eating between 5:45 and 6:15; this gives you plenty of time to do 1 or 2 shows, then be back to your room around 10:30 or 11p.
You may also want to "tag" your luggage with something "big". I use the colored bath sponges @ Walmart for $1.99. Everyone uses "ribbon" and when you retrieve your luggage; it isn't very noticeable. I also have used felt material in red/yellow & green (cut into 4" squares with a hole cut in the middle of all 3 swatches then wrapped around my suitcase handle with a pipe cleaner) It makes finding your bag easier. I also would recommend if you shop a lot to take an extra/empty duffle bag. Also take #30 or 45 sunscreen.
I hope you enjoy your trip. We've cruised at least 10 times and Princess is our most favorite (compared with HAL or Carnival).