I've done a few via Royal Caribbean, always pretty good, we recommend them simply because they put on a good show, have clean and updated ships, and the food is nice.
Book directly, pick a route with some interesting stops, do a shore excursion or two. Enjoy.
PS. The drink package is rarely worth it, even as someone who drinks a good amount on vacations, it's hard to break even. More-so if you're doing stops at places not owned by the cruise line.