I've stayed at the Pullman near the Miami Airport. Have stayed there either three or four times in the past. They have a free shuttle from the Airport and will also shuttle you to nearby places (although they are walkable). Right around the corner is a strip center with a Cuban Restaurant, Starbucks, Publix along with a few other places to grab a few things. In the parking lot is a Burger King, which is good if you're not wanting a full meal. Across the street from the Strip Center is a Walgreen's and of course across the street from Walgreen's is a CVS. Both the Walgreen's and the CVS are good for those last minute things you may have forgotten to pack, such as sunscreen or other assorted sundries.
The concierge at the Pullman can also arrange for transportation to the Port on your day of embarkation. I think the cost is either $10 or $11 per person.
The Pullman is one of the hotels NCL uses in Miami for pre or post cruise stays and they have their own shuttle which will pick up NCL passengers the day of embarkation. I've booked the Pullman both ways and have saved money either booking through Trivago or the hotel's website.
Good Luck with your selection.