I haven't sailed with
DCL out of Miami's port yet, but have sailed on other lines. We will be taking the Wonder in November, so I'm looking right now.
The Miami International Airport Hotel (actually *in* the airport) is older, but really convenient, since it's located in Terminal E. It used to be a Hilton, but apparently isn't any more. If you're coming in the night before, it's as convenient as the MCO airport... but smaller, a bit older, and no pool. It does have a lovely restaurant at the top floor you can watch flights from though!
Post cruise, we'll be booking a "day-rate" room, since our flight doesn't leave until 6pm the day of disembarkation. 2 beds, a shower, a tv, and the ability to watch the airport monitor from the room make it worth it.
I've also stayed at the Holiday Inn Port Miami down by the docks before. It was clean, quiet, and you could see the ships out the window in the morning. Plus there's some little shops you can wander around nearby.
Unfortunately, it's fully booked for our night before already. The Intercontinental gets good reviews.
Either way, it's really much easier to get to the port in Miami than to get to Port Canaveral from Orlando, no matter where you stay.
If you're flying into FLL instead of MIA, definitely check tripadvisor and look for something down by the port!