First, you definitely want to work with an agent who is a Cruise Specialist. They'll be happy to assist you and answer all your questions.
As for the NCL Dawn, we were on it a few years ago - nice ship, but we personally found the food only so-so. And while we've been to Bermuda, it wasn't on the Dawn - it was on the RCCL Explorer of the Seas. Love Bermuda, but thought the Explorer was a nicer ship than the Dawn.
As for getting a mini-suite connecting to another cabin, if you're talking 8 adults, I definitely would not suggest it. If it's two adults and two kids, it's not a problem, but four adults in one cabin is not something I would consider.
There are many options to consider - talk to your agent and they'll help find you the best cabins for you based on your requirements, budget, and lifestyle.