Cab fares are fairly cheap & reasonable. Most hotels offer free shuttle service. We did not stay in MIAMI itself but we book in Ft Lauderdale @ the embassy suites which is around the corner from the princess dock. We met alot of folks going on Caribbean Princess that where also staying at the hotel.
The hotel sits in the center of many restaurants. They have a big outside pool with it's own waterfall. The rooms are very nice outside the balcony you can see the princess dock and other ships docked.